A manager, an engineer, and a web programmer are riding in a car. They come to a hill and their brakes fail. After careening down the hill and finally coming to a stop they get out to decide what to do.
The manager says “We need to have a meeting to form a committee to see what we should do next!”
The engineer says, “No way! Give me a pocket knife and some duck tape and I’ll have us going in no time!”
The web programmer looks at them both and says, “Lets push it back to the top and see if it does it again.”
Ahh, the life of a web programmer. That person you toss all your meaningless tasks to, the one that works silently behind the scenes reading hundreds upon thousands of lines of code just to explain why your users can only log-in on days that end in "Y" but not after 3am and before 6pm.
Reproductability is the best tool a web developer has in troubleshooting. Just like with most problems, being able to see it first hand is the first step towards a resolution. The more information the web developer has, the quicker he/she will be able to pinpoint the issue (or behavior), document it, and let you get back to crushing that candy.
So, your web programmer, be them friend, nemesis, or hero.... Your users CAN log in, the username and passwords are case sensitive.
Image thanks to harshadpd.deviantart.com