There may be a decision making process on the client's side about whether to accept the new hotfix, maybe they have a workaround for the broken functionality or maybe it's just not worth the risk to them.

Then you might create another hotfix while that decision making process is going on, and both you and the client need to evaluate whether it's possible and desirable to apply the first one, second one, or both.

It's why versioning, source control, build process automation, and client communication are so important to get right from the outset.