Most of the meltdowns I have seen in children and adults are due to sensory overwhelmed. Some of the meltdowns may also be due to becoming frustrated on something they can't figure out or mentally deal with.

I have meltdowns when critisized about my laziness. My laziness is usually due to feeling overwhelmed or weak. So I attempt to correct the problem and instead end up shutting down further to the point that I am basically catatonic.

I do better with suggestions on something that needs to be taken care of by me, but recommendations on how the critisizer can help me accomplish that goal. That keeps me from getting emotional. I still might not be able to do the task, but at least I can then respond about what is the problem and why I am useless at the moment.