What’s wrong with this zucchini?

What’s wrong with this zucchini? The one on the left is yellowing and shriveling up. It wasn’t either fully pollinated (some bee didn’t do her job) OR once again it was too hot when pollination happened and it didn’t take hence it is self aborting. Just like tomatoes, all squash likes the heat but not when it is trying to pollinate. The zucchini on the right side of the photo is fine.