It's a shame when things don't work out the way people expect them to, especially when something is lining up to be perfect, when it's looking great, and then it all comes crashing down.

This happens a lot with marketing since things tend to look 10 times better on the ad or in the photo than they actually are in real life, and it's always super upsetting. Take fast food, for example, that burger in the ad will never be the one that comes through the drive-thru window. Or the frozen meals in the grocery store — no way the microwave is making that gourmet dish.

Sometimes we do it to ourselves, too, with ambitious baking projects or crafts. It happens to everyone from time to time, and users can share their most disappointing moments at Reddit's "Expectation vs. Reality" community. This place is full of sad comparisons of expectations against their realities.

Here are 15 of those very sad but very real times, and some of them are pretty bad.