I've read a few articles recently that argued that ideas, by themselves, are worthless. According to these writers, it's only when an idea is implemented (e.g., when a startup takes the idea to market) that it has value. In support of their argument, they cite the belief that angels and VCs pay much more attention to the team than to their idea; a great team with a bad idea can find a better idea, but a mediocre team, even with a great idea, is likely to fail.
I disagree with the argument that ideas are worthless. Every business starts with an idea, and if it's a bad one, the company will probably fail unless management recognizes the problem in time AND finds a better idea to implement. A good analogy is between potential and kinetic energy. An idea by itself has potential energy that can be released (converted into kinetic energy) if it's implemented properly. The better the idea, the more potential energy it has.
There are great ideas with tremendous potential that can't be released, because they're ahead of the market or the available technology. That doesn't make them worthless--it just means that they need to be put on the shelf for a while. There are equally great ideas that are implemented by mediocre teams and fail, not because the idea isn't good but because the team implementing it bungled the job. The implementation of the idea was bad, not the idea itself.
As for VCs and angels who believe that if a "great" team has a bad idea, it can successfully pivot and find a better idea, consider that for even the savviest investors, 70% of their investments fail completely, 20% survive but rarely return more than their initial investments, and if they're very lucky, 10% succeed and are either sold for a big profit or go public. In my opinion, it's at least as likely that the "great" team will go from one bad idea to another until it runs out of capital or blows apart.
One other point: The definition of a "great team" is very speculative. Enron had a widely respected management team, right up to the point that it imploded. The top management of the major commercial and investment banks were considered "Wizards of Wall Street", even though they didn't understand the financial instruments that they were buying and selling. We didn't find out how incompetent they were until they nearly dragged the world into a new Depression. It's very difficult to identify the teams that are going to work well before they've actually spent a considerable amount of time working together on the idea that's being funded (not based on their previous experience working together at other companies.)
Therefore, the quality of an idea is at least as important as the team executing it. If you discount the value of ideas, you do so at your peril.