When to "heart"

I don't know if any other ladies have this problem, but sometimes my husband just can't climax. He will start out okay but then slowly get soft and not be able to O or ejaculate. Do you still mark a "heart" on your calandar even if he can't quite get there? 
Part of me wants to mark it because sex is sex and I guess there's always the chance of pre-cum, but part of me thinks that because there wasn't a full on blast (LOL) that I should mark that we didn't have sex.
Any responses would be appreciated. Thanks ladies!