Football is a short-term business.
The rewards are too great and penalties for failure too severe for it to be anything else.
It's why managers who work tirelessly to get their club promoted into the Premier League are sacked a few months later.
It shouldn't be a surprise that of the three clubs promoted from the Championship last season, two got rid of their managers.
It can happen to anyone. Roberto Di Matteo was sacked by Chelsea just six months after winning the Champions League.
Manuel Pellegrini only took over at Manchester City last summer, but he is already the eighth longest-serving manager in the Premier League. It tells its own story.
Even Manchester United, held up as a beacon of hope for those who think football clubs should look beyond next Saturday, discovered this season how hard it is to choose stability.
That was the plan. When they gave David Moyes a six-year contract they fully expected to honour it. But that was before the disappointments. So many disappointments.
The trouble for any manager is that a long-term plan has to be backed-up by short-term success.
It's all very well chucking a load of homegrown kids into the first-team. But if the team isn't winning, the goodwill isn't going to last very long. Just ask Paul Lambert.
United have always tried to produce their own players. It's become part of their identity. But it's no coincidence that the two managers best known for it, Sir Matt Busby and Sir Alex Ferguson, enjoyed long reigns at Old Trafford.
They married long-term goals with short-term gains. They felt confident enough to trust young players because they were secure in their jobs.
The academy Ferguson helped build at Carrington is still producing. James Wilson is the latest to announce himself after two goals on his debut against Hull.
But it's debatable whether Ryan Giggs would have made the bold decision to start with Wilson on Tuesday night if his job, or United's season, had depended on the result.
Giggs knows he won't be manager next season, and United have nothing to play for. Consequently, 18-year-old Wilson and 20-year-old Tom Lawrence were thrown in at the deep end.
But the minute United sacked Moyes, they showed they value short-term success above anything else. It is something Louis van Gaal—if and when he takes over—will be aware of.
He will be charged with getting United back in the Champions League—at the very least. And that's not a climate conducive to developing players.
Van Gaal has a history of putting his trust in academy graduates. He's been successful with it at Ajax and Bayern Munich, in particular.
But it won't be his first thought when he walks through the doors at Carrington. How can it be? In the short-term, he will be judged by the games he wins and trophies he collects. He's managed enough big clubs to know that.
At 62 years old, it is difficult to see the Dutchman as a long-term appointment. He will be expected to rebuild the squad with new arrivals and get United back into a position to challenge for titles.
His record suggests he's capable of doing it. But it may come at the cost of the long-term vision championed by Busby and Ferguson.