The mistake isn’t falling behind. It’s deciding you’re too far behind to try.

Falling behind is a position, and positions can be worked from. The costly move is the conclusion that the gap is now too large, because that turns a recoverable situation into a permanent one by removing the thing that would close it. Most people who never catch up stopped for that reason, not from any impossibility.

Take whatever you have written off and do ten minutes of it today, badly. The point is not to catch up today, it is to stop the decision from hardening. If it is a class, go and ask what the minimum route back looks like, because it is usually shorter than you assumed.