As it is in any sport, pressure is ever-present in Formula One. Every team and driver feels it to some degree or another; the pressure to find performance, maintain it, build upon it and push on to greater things.
Ferrari are under massive pressure to make a genuine return to the front of the grid, while Red Bull feel the constant weight of expectation to produce a field-leading chassis.
Renault will want to do the best they can on their return as a constructor; Williams will be aiming to retain their position as top independent and the staff at Mercedes have the weight of the world on their shoulders as they strive to make it three doubles in a row.
The smaller teams have other pressures—mostly financial—while Haas can ill-afford to turn up unprepared and uncompetitive after so much bullish talk in 2015.
But the troubles of the rest of the grid pale to relative insignificance when compared to those faced by two of the sport's most famous names—McLaren and Honda.
McLaren had arguably the worst season of their long and proud history in 2015. For the first time since their very first season—in which founder Bruce McLaren started just four races for his own team, all the way back in 1966—they failed to achieve at least one finish of fourth place or higher.
The team's final position of ninth in the constructors' championship was their worst since 1980, and their two world champion drivers—Fernando Alonso and Jenson Button—ended up 16th and 17th in the drivers' championship.
McLarens made no appearances in Q3, suffered 11 race-ending technical failures and were lapped far more often than not. Their underpowered, unreliable Honda engine was the primary cause of their woes, but the MP4-30 chassis wasn't perfect either.
Even if their Japanese partner had produced a power unit to rival Mercedes, McLaren would not have been anywhere near as quick as the two Silver Arrows.
In isolation it was a terrible season, but this was only the latest in a string of disappointing years. Since winning the 2012 season finale in Brazil, McLaren have entered 57 races and been on the podium in only one of them.
They haven't had a pole position for more than three years, and the last time a McLaren set the fastest lap was at the 2013 Malaysian Grand Prix.
Their recent results look like those of a plucky, underfunded midfield outfit—not those of a wealthy team with cutting-edge facilities, brilliant staff and glittering history of success.
Failure is not a part of McLaren's DNA, and drivers do not join the team expecting to be anywhere other than at the front.
When Alonso signed for the team at the end of 2014, he cannot have been expecting a season as bad as the one he just endured. Likewise Button, a McLaren man since 2010, won't have imagined in his worst nightmares that he would ever have to drive a car like the MP4-30.
Faced with a package as bad as the McLaren-Honda, a younger driver yet to prove himself might have been able to find the motivation to perform at his absolute limit. But both Alonso and Button—proven winners and champions—have admitted they struggled in 2015.
At the beach #PlacesAlonsoWouldRatherBe #F1 #BrazilGP https://t.co/w2EW3GEsD62015-11-14 18:06:36
Alonso revealed to BBC Sport late in the year that he was on "economy mode" and found it difficult to motivate himself, while Button came close to retiring from F1 altogether.
His demeanour at the Singapore Grand Prix was unusual, leading many—including Sky Sport's Ted Kravitz—to believe he was going to leave at the end of the year. This viewpoint was only strengthened by comments Button made after the race.
He told the assembled press, including the Guardian's Paul Weaver:
The joy of being in the car is only there if you’re fighting at the front, because you feel like you’re achieving something.
If you’re fighting near the back you’re driving an F1 car, but you can easily get joy driving something else. The joy you get is competing. It’s about fighting at the front. It’s about the possibility of standing on top of the podium. That’s the joy of F1.
Button eventually decided to stay, while Alonso elected against taking the sabbatical McLaren boss Ron Dennis had hinted at.
But if 2016 goes as badly as 2015, will either driver want to stick around?
The loss of Button would be acceptable to McLaren, given what they have in reserve—but keeping Alonso, widely regarded as one of the very best drivers on the grid, is critical to the team's short-term future.
Unless they have a substantial performance advantage, a top team needs a driver capable of pushing the car beyond its limits and fighting against the likes of Lewis Hamilton and Sebastian Vettel.
If Alonso decides he's had enough of being near the back and leaves, they will not find it easy to attract a replacement. The only driver on the grid who has even started to prove he is ready to join the elite is Daniel Ricciardo, and a risky switch away from Red Bull to a struggling McLaren is unlikely to appeal to the Australian.
Nor would it be attractive to other up-and-coming talents—the likes of Valtteri Bottas, Romain Grosjean or Max Verstappen. Not that they, at this time, could be considered like-for-like swaps for Alonso.
For McLaren to retain their status as a "top team" capable of attracting the sort of drivers who can win races and titles, they have to start performing like one.
If they can't, their road back to the front will become longer and harder—and the relatively minor money troubles they are already having to deal with could become a major long-term issue.
McLaren's finances have taken a severe hit after three disappointing seasons in a row. Though they receive a bonus from the commercial rights holder due to their historic success and longevity, a significant portion of the team's income is performance-based.
Per figures published by Dieter Rencken of Autosport (figures for 2014), a third-place finish—which McLaren achieved in 2012—is worth $73 million in prize money.
Fifth—where they finished in 2013 and 2014—is worth $63 million, while the ninth place they took last season only brings in $48 million.
Working by necessity from the 2014 figures, McLaren earned $25 million less in 2015 than they did in 2012. The extra $34 million they receive as a bonus means this won't hurt them as much as it would a smaller team, but coupled with the loss of sponsorship income the picture becomes bleaker.
At the end of 2013, McLaren's title-sponsorship deal with Vodafone came to an end. This deal was, per the Financial Times (h/t James Allen), worth $75 million per year—and McLaren have been unable to attract a replacement.
Instead, they have lost backing. Hugo Boss departed at the end of 2014 and Tag Heuer switched to Red Bull at the end of the 2015 season. Chandon arrived as a sponsor in late September last year, but there was speculation, reported by Pablo Elizalde of Motorsport.com, that this could mean the end of McLaren's association with Johnnie Walker.
On the positive side, rumours that the team's deal with Santander was about to end were put to bed in December when a new agreement was announced, and Honda are contributing a significant sum to the team budget—around $60 million, according to the Telegraph's Daniel Johnson.
McLaren also have other ventures outside F1 that can be used to prop up the racing operation, so it would be an exaggeration to say they are in a major crisis. But the team's finances are still on shaky ground—further figures from Rencken suggest they spent around $30 million more than they made in 2015.
Such losses are not sustainable.
They need to attract large, wealthy sponsors to enable them to keep spending like a top team, and to do that they need to deliver on the track. No sponsor wants to be associated with failure—podiums and race wins are essential for a team demanding big money for the space on their cars.
But one thing sponsors do like to be associated with is world champions, and that's going to throw up another hurdle for the team management to deal with around the middle of 2016.
In Stoffel Vandoorne, McLaren have the most exciting young talent yet to make his F1 debut. Had the 23-year-old been a part of Red Bull's successful junior programme, he would probably have made his debut at the start of 2014.
That's when he was ready.
Instead, he has just left GP2 on the back of two seasons in which he shattered almost every record in the series. On his way to scoring more points than any driver in GP2 history, Vandoorne won more races (11), took more pole positions (eight) and scored more podiums (26) than anyone before him.
He did this in just two years; those he deposed at the top of the rankings were veterans of three, four or even five seasons.
But rather than making a richly deserved step up to F1 for 2016, Vandoorne will be wasting another year of his career as a reserve driver for McLaren.
A younger man could afford this, but Vandoorne is no teenager. He will be almost 25 when the 2017 season kicks off—Vettel, Hamilton and Alonso had already won world championships by that age, while Ricciardo, Michael Schumacher and Robert Kubica were race winners with established F1 credentials.
Indeed, Vandoorne will be positively ancient by modern rookie standards. The average age of the five debutants in 2015 was 21; he's already years behind younger drivers like Max Verstappen, Daniil Kvyat and Carlos Sainz Jr.
McLaren will not be able to hold him back again, and with no junior team in which to place him they will be back to where they were in 2014 and 2015—umming and ahing over the future of Button.
The sponsors and many fans will surely favour keeping the 2009 world champion, but McLaren must realise Vandoorne represents the future. If Button doesn't take matters into his own hands and retire, as he almost did last season, the team management will have to make a decision for him.
More pressure the higher-ups could surely do without.
McLaren are still, by some distance, the second most-successful constructor in F1 history—but in recent years, they have failed in every department.
They have failed on the track, they have failed to attract new sponsors and—if we extend the definition of "team" to include the engine supplier, which in fairness we always should—they have failed to get to grips with the new regulations.
They've also inexcusably failed at looking after the careers of talented young drivers.
In 2016 they have to reverse the trend in every part of their operation. No one expects them to suddenly start dominating, but if they wish to attract new sponsors, retain their position as an acknowledged "big team," keep Alonso interested and shed their reputation as a place young drivers go to see their careers stall, McLaren have to at the very least show strong signs of progress.
A big step from Honda, a genuinely good chassis, a new sponsor or two and the odd podium would be good places to start.