"I have not failed. I've just found 10,000 ways that won't work." - Thomas Edison

Allegedly he didn't actually say that but expressed something to a reporter in the spirit of it, so close enough.

Anyway point being that not making explicit progress in something is (at least a good amount of the time) still progress. As in in order to do the thing that you wanted to do you had to resolve that issue you didn't know about first. So that was a necessary step along the way.

For more specific problems (like those of mostly technical nature in game development), this approach is plenty. For more abstract lessons (of the sort related to broader project scope management and large macro game design decisions) certainly it's less applicable, and less guaranteed (because ability is not necessarily linearly correlative with time investment). In any case, even if a big project burns down at least you've strengthened the technical skills you used to make it.