"The first thing that came to mind was something that happened many years ago. One year I faced a large income tax bill and couldn't pay it all at once. The IRS said that I could make payments on the amount until the tax bill was satisfied. Then the rep told me that I'd be getting a nasty letter from the IRS every month, which I should just ignore. I don't know about Rich's four cents, but the "DM yourself" issue and my IRS issue show that software truly IS hard. It's hard to anticipate every possible scenario in software - the Twitter folks apparently never asked the question "what if someone DMs themselves?" and the IRS folks never thought to account for payment plans in their software. And even if you could account for every conceivable scenario, would you want to take the time (money) to test for all of them? It's a balancing act." - John E. Bredehoft