A lap counted honestly is useful even when it is fewer than you hoped.

An accurate number you dislike is worth more than a generous one you enjoy. The count that disappoints you is still telling you where you are, which is the only place any improvement can start from. Rounding up feels better for an hour and costs you the ability to see whether anything is changing.

Keep one measure this week without adjusting it. Laps, minutes, pages, whatever you are working at, and write down the real number even on a bad day. Over a few weeks the low entries turn out to be the useful ones, because they show you what the average actually is.