It used to be when ur breeding temple ran out of time and ur egg wasnt finished u got all ur time back that remained and if u gemmed the remaining time b4 the temple ran out it would stay done. NOW if ur egg is finished(during the temple discount) and it isn't in the hatchery b4 the temple runs out u get all the time leftover even if it was already done. I can't see any reason for it other than it being another way for Sp to force us to use gems. The way things are now during these events and their bs success rates its impossible to have an empty slot in the hatchery at all times with the amount of epics u get and at 37 hrs/ epic to hatch and only a 7hrs to breeding after 4 attempts ur in the hole for 30 hrs until ur next slot opens up.

Those breeding event are gems trap , that is why many avoid it
and the monster featured goes usually for sale later , SO if you don't like gambling then wait for the offer instead

I always have a problem with the words they force us to use gems, no they don't they don't force you have a choice don't spent more then you want to because as @Haka-Taka it's a gamble and when you gamble you can lose but nobody is holding a gun to your head

@Marianne-van-Es you put it so well. All of the games out "ENCOURAGE" you to spend money to get the best gear, to speed up events, to get the most exclusive characters.

You have to decide if you are going to spend, and on what. It all comes down to what you want, and how much you are willing to spend.

The app developers have overhead, employees, benefits, etc. to pay. They are in business to turn a profit.