[Add!ction]

Do universities sometimes accept you if you miss the grades and haven't phoned them up or anything?

[TheSownRose]

Sometimes, yes. It depends on whether they have any places left over, how well you compared to other misses and how competitive they thought the course would be in Clearing, amongst other things.

Incidentally, phoning them on results day is unlikely to reverse a decision - the university has already had the better part of a week to mull over your results, so unless you have new information (like you had a remark and the grade went up), don't pin any hopes on it.