Other people may see things that you don't, or suggest beneficial things that you would not have thought about on your own.
That's true for lots of things in life. Having someone else give us a little perspective can go a long way.
My mom has a few apples trees that we didn't prune for a few years. When it got done, it was painful to watch all the branches go, but the trees have been much healthier since then. And those branches that just go straight up, but don't produce fruit are gone!
It looks drastic for sure, but it benefits the tree and the people eating the fruit!