probably, but doing the same thing over and over again manually is even more error prone.

Sure - but I am guessing a few errors here and there would have much less impact than a single programming mistake. Not that I think this is the right way, but I do understand where they come from.

Human error was much more common. But they did have another tool for reconciling trades that was better. It was web based and auto reconciled most things that were obvious matches. I don't recall why, but they were not too concerned with mistakes so long as we could fix them by the end of business. I think it was because that's when clients would see something was off on their statement/account. There was never a concern of losing money. I wish I could remember why, but this is my cumulative experience in banking industry and I quickly forgot everything I learned.