A common misconception is that entrepreneurship is all about coming up with great product ideas. There's a lone genius who has a eureka moment and afterwards the outcome is preordained.
This view is far too naive. There's certainly a lot more that goes into building a successful company. An idea alone with zero execution is worth (almost) nothing. Moreover, there are many examples of companies that failed where their competitors succeeded even though they started earlier with exactly the same idea.
As a response to the naive pop culture view of entrepreneurship, many experienced entrepreneurs feel the need to go full contrarian by saying that "ideas are worthless" and that "execution is everything".
This view is far too extreme. A silly idea executed perfectly will not result in a successful business.
Ideas certainly matter, just not to the extent and in the way that most people believe.
A more balanced and realistic view is that ideas are just a multiplier of execution. To illustrate this idea Derek Sivers suggests to consider the following numbers:
AWFUL IDEA = -1 WEAK IDEA = 1 SO-SO IDEA = 5 GOOD IDEA = 10 GREAT IDEA = 15 BRILLIANT IDEA = 20
NO EXECUTION = $1 WEAK EXECUTION = $1000 SO-SO EXECUTION = $10,000 GOOD EXECUTION = $100,000 GREAT EXECUTION = $1,000,000 BRILLIANT EXECUTION = $10,000,000
The potential of each business is a product of two such factors. A brillant idea with no execution is maybe worth around $20.
A good idea with good execution is worth $1,000,000, and only when a brilliant idea is paired with brilliant execution, you end up with a billion dollar company.