For one datapoint, I've participated in many gamejams and I've never ever spent any time beforehand thinking about ideas.

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sarchertech 3 days ago | parent [-]

How many big game jams have you won/placed very highly in though?

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deadbabe 3 days ago | parent [-]

Game jams typically require games to adhere to a theme that is only known the day of, and the best entries will make a game specifically around that, not just adapt some pre-existing idea to it.

	▲	sarchertech 3 days ago \| parent [-]
		The themes are so open ended it’s very easy to adapt most game ideas. Games that win tend to be the most fun to play not necessarily the ones that fit the theme the best.