Races are lost by people who slowed down because the finish line was in sight.

Seeing the end releases something. Your body reads the finish as already achieved and quietly stops spending, so the last stretch becomes the slowest one without you ever choosing to slow down. Anybody still working through that stretch goes past you. The same pattern shows up in projects, terms and shifts, where the final tenth is exactly where attention leaks out.

Decide in advance where your effort ends and put that line past the visible one. In the last stretch, check whether you are still working or just coasting. Finish, then celebrate.