If you watch college football, you might say route running is overrated because of all the screen and Go routes being thrown. In contrast, when it comes to the NFL, route running is the most important trait of all wide receivers.
When a receiver can't run routes properly, he doesn't separate from defensive backs the majority of the time despite his physical traits. This means he must understand the nuances of route running, which includes beating press coverage, not wasting steps and tipping off defensive backs with their eyes and shoulders.
Most of the league's best receivers are exceptional route runners and don't make the aforementioned mistakes in the process, which is why they are considered elite.
But as you'll see over the next few slides, not all elite receivers are exceptional at it and some aren't even in the Top 25.