Perhaps because this man knew, unequivocally, that he was actively being murdered? That is usually a process accompanied by some discomfort regardless of method.
What is the perceived benefit to removing a trampoline enclosure, though? It doesn't make the kids have more fun, it just makes the activity riskier (and trampolines are pretty much death traps). I say this as someone who had one as a kid (no enclosure) and would probably buy one for my kids (with enclosure).