Many people dismiss mathematics because they aren't interested in it. I definitely wasn't interested in doing dozens and dozens of error-prone problem sets that mainly boiled down to performing arithmetic. I don't need to do that.

My number theory professor was a brilliant mind, someone who had spent lots of time at the Institute for Advanced Study, and he absolutely sucked at adding/subtracting/multiplying numbers. And that was something he freely admitted. It wasn't important to his work, and it isn't important to mine.