This is a trivial observation.
However, it is often used as a defence to mean:
'If I react badly internally, or behave badly externally, I am not responsible. It is inevitable. I am not to blame. No one can reproach me. I am under no obligation to address this, to uncover the cause, and to correct it. Please change the subject.'
(It is, of course, used in other ways, too.)
What is the truth?
Immature, unhealthy, or unhelpful actions and reactions are inevitable over the course of one's life, but that does not mean that any particular action or reaction is inevitable.
When it comes to reading out loud, every word is pronounceable by me. If I do not know how to pronounce it, I can learn. The resources are available to me. It is a matter of concentration and effort.
When I am actually reading a passage out loud in a performance situation, I am bound to make a mistake somewhere, if I read for long enough. That does not mean any particular error is inevitable.