Missing a day.
When we miss a day on a habit we are trying to build, the immediate reaction is to try to make up for it the next day.
That's a trap and it leads us on a slippery slope which goes like this: if you write a blog daily, you should write two the next day. If you walk 5 km every day, you should now walk 10 km the next day.
This doesn't make any sense. It would only make it more likely that we would miss the next day too and that's when we are likely to completely fall off track.
Instead, if we have missed a day, the best we can do is to continue as if we haven't. Even better, we can try to make it a bit easier the next day.