Actually we don't. Because the likelihood of someone else executing as well as you depends entirely how far out towards the edge of the innovation bell curve you are.
Beyond a certain point you can't be copied because you're literally the only person or company in the world who can execute.
Obviously this depends on talent. Mediocre talent is much more widely available than exceptional talent. So if you're not exceptional, you'll be copied.
If you're talented you can be first to market, but you'll be copied sooner or later.
But if you're truly exceptional you can't be copied at all, because you'll be combining exceptional imagination, exceptional execution, and exceptional access to resources. If you happen to combine those and provide something enough people want, you win your niche.
At this point you can only be imitated poorly. Sometimes that's enough to for competitors to survive around you. But it's a precarious existence, and if you continue to innovate you'll always be ahead of the competition.