Their kid was ill, their partner had a thing, they didn't remember another event that they had previously agreed on, they said yes but they were thinking of another date, "is it for that game? I thought we were gonna play something else.", that's a long weekend week so they had out-of-state plans, etc.. etc..

I sometimes feel bad for DMs.

Edit: If I say I'll come, I will come, I'll force myself. Otherwise laziness will get the best of me. Few things I own, better to keep my word.