How do you carve an elephant? Get a block of marble and carve away everything that isn't an elephant.
The failed process of game design goes as follows:
*Flash* Brilliant game mechanic, looks like fun. This will be huge. It's perfect.
How should the turns play out? Could be one at a time or simultaneous. I'll decide later. Should I add a board or just use cards/dice? A board's superfluous. Then again, it's more substantial than a card game.
How should the game end? A set number of round. No, until someone reaches a certain number of points. No, when the deck runs out. No, ... So many options! OK, I'll decide later.
How should the scoring go? 1 point per card. No, per set. No, more points are earned in later rounds. No, collect point tokens. No, print the points on the cards. No, ... ok, I'll decide later.
Wait a minute. Let's combine this mechanic with this other game prototype which has been sitting around. It makes a great fit. Now my simple mechanic is combined into a game that looks like a six hour, fifteen step civilization game from the 1980s with route planning, area control, auctions, set collection, special powers, mission cards, and the kitchen sink thrown in for good measure. (I've done this before.)
What was the mechanic again? Yeah, that, but it favors the first player. No, it allows a kingmaker. No, it makes for no way to catch up. No, your decisions don't matter enough. No, there's no way to stop people from ganging up. No, there's not enough interaction.
There's too much luck. I can eliminate the cards/dice in favor of selecting or an auction. No, then it's too dry and mechanical.
Why did I think this was fun again? I think I'll shelve it and get back to it.
(Repeat every day)
Lack of ideas isn't the problem.
Knizia is a successful game designer not because his ideas are better than anyone else's. He just knows how to avoid all this nonsense.