One simple reason why I need to try myself doing some home repair is that M is not always at home. So if there are some minor stuff that need to be repaired and done immediately then, I have no one to trust to work for those but myself.
Some of the things I’ve done are just changing the bolt and tightening the grippers. But when I used these, at first, I really had hard time perfecting it. And of course, as what many said, practice makes one perfect, after two or three tries, I finally made it. Good enough M was satisfied with my work when he arrived home and checked my output.