Why do people kill themselves at the beginning of horde matches?

It’s not annoying at all to me. What is annoying is when people leave because someone didn’t kill themselves.

Or they start cussing out the heavy on mic and degrading and belittling them because they won’t/don’t know how to do the boom trade with engie or sniper.

That kind of uppity ■■■■ annoys me. Actually enjoy playing with newer people so long as they’re legit and not selfish trolls.