You have to get in the endzone, once again a receiver mistake.
I disagree. This is often an argument, especially regarding the first down sticks. What people fail to realize is that if he doesn't come back to that ball, there is no catch in the first place so its a moot point. The other side of the argument would be to run the route a yard deeper, but that would also affect the outcome of the play, changing the timing, changing where the defender is etc.
This is the most ridiculous, played out argument I have ever heard by commentators at every level. You can't just "get that extra yard" and have everything else happen exactly the same. It doesn't work that way.