I didn't understand their comment to mean that at all. It's not arrogant to think there might be a better way. It probably is arrogant to think that the better way is actually really simple and easy to implement.

Arrogance definitely can play a big role in success of many startup entrepreneurs. Because they think the answer is simple and their arrogance shields them from not trying. So they go down the road and find out the solution is actually quite complicated, but a small percentage succeed in accomplishing the goal.

But it's still arrogance, nonetheless.