I’ve been working on the Web since 1998 and the ability to trap “internal” errors became available in Microsoft IIS in 2000. Ever since my web applications have hidden all error messages from users (and either save them in the database or email them directly to me) and instead provide a “user-friendly” explanation of what happened and what to do next.

If a site doesn’t do that, I attribute it to the laziness or total inexperience of the programmer in charge. There’s no excuse.