It isn't always a job. Sometimes it's just tinkering. Sometimes it's grandma trying to make sense of the Ubuntu linux install her grandson just replaced an old virus-laden version of windows with. Or the unfortunate retail worker on the phone with support staff because her POS terminal can only boot into single-user mode. Or (and I have experience with this one) an account manager at a customer install site trying to fix a bad update.
I have not worked with many things they require of me either. Before I apply, I either have to learn the very basics, or I will have a hard time, unless they do not mind me not knowing but learning fast.