It’s great to aim way higher than you can attain. You aim high and you hit low. But that’s still pretty high. Way higher than if you settle for junk.
But unrealistic expectations without understanding that they’re a motivational target at which you are aiming will cause a great deal of disappointment and destroy your will to keep pressing on.
Aim high, but just for the sake of raising the floor of what’s possible. Be a 7/10 by aiming at a perfect 10. Or you could be a 4 because you decided not to aim at all.