What do you call something that everyone says will happen but never does?

Is there a term for something that lots of people say is going to happen, but it never happens (at least in the immediate future)?

For example, say everyone says "the tech bubble's going to burst" - yet it's 3 or 4 years until it does.

Is there a generic term or phrase for this concept?

I don't think this always has to be an alarming situation. It could be something like "Xbox prices are going to go up", but they never do. More like a prediction that never happens.

Solution 1:

I can think of many terms for an event that occurs or passes, but without the expected result; for example, a nonevent, a false alarm, or a damp squib. For example, you could say:

The Y2K bug got a lot of press, but in the end it was a nonevent.

For something less well-defined, like the tech bubble, you might say it defied conventional wisdom. There's also a specific kind of expression sometimes used in technology: if something is hotly anticipated or talked about as being imminent, but never quite gets there, you might say:

I don't want to wait for that tech to be ready; it's always five years away.

Or:

Don't get too excited about the new cold fusion study; that tech has been five years away for fifty years.

Solution 2:

Usually we call that a false alarm.

a warning that is given about something that fails to occur

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