I'm looking for a word or phrase that encompasses the following series of events:
- Something is a great deal.
- Many people see that it is a good deal and buy it, invest in it, or similar.
- So many people do so that it becomes a bad deal.
One mechanism by which this might happen: It's a good deal because it draws on a shared, finite, but abundant and mostly untapped resource, perhaps a natural resource or a fixed amount of money. When many people pursue the deal, that resource gets depleted or stretched thin, causing it to be a mediocre or bad (net loss) deal. Perhaps just the last people in lose out, but because of the exponential growth of the knowledge of the deal, that's half the people involved. Or perhaps everyone, even the earlier adopters, lose out.
Examples: (but ignore the part of speech)
The CD class action settlement would send up to $20 to everyone who opted in the class. But so many people did, that it was a << phrase >>; my check was for 37 cents.
In a << phrase >>, after the traffic reporter said the I-495 had light traffic, so many people shifted their routes to it that traffic got snarled.
This place is awesome, except for the crowds.