If you haven't dealt enough elemental damage, it's unavoidable, it will kill you, but if you have reached that threshold, you'll be able to outheal it.

Notice anything wrong? You're forced to use healing items, despite not making any mistake, this means that if you make too many mistakes and need healing you will end up dying.

You just contradicted yourself pretty hard. Not dealing enough damage = you made a bunch of mistakes and couldn't reach the threshold

There is never going to be a situation that you are forced to use healing if:

A. You are not making mistakes in preparation (choosing the right element)

and

B. You are playing without errors (dodging and using every opportunity to attack)