In any start-up, there are hundreds of decisions to be made. From "what business should we be in?" to location or logo, the founding team needs a healthy dynamic around how those decisions are made. In each decision, there is usually a champion, a skeptic and an arbiter.
The champion typically says "wouldn't if be great if..." and focuses on the upside of the decision. The skeptic says "that is risky/costs a lot/is de-focusing." And the arbiter is in the middle weighing the relative tradeoffs.
A few key thoughts are:
1. Be aware of this dynamic
2. There are many decisions to be made. Note if the same person is always in the same role. If so, then intentionally switch up the roles. See "Six Hats Thinking" for a related analysis of this idea.
3. It's tough to have a healthy dynamic in this regard if you don't have three founders. So, this reinforces the idea that 3 founders is the right size for starting something (big enough to get stuff done, but small enough you can stay coordinated.)
So healthy teams have an awareness of these roles, rotate them frequently and are not overly-invested in any particular decision. If your point of view does not carry the day on this issue, there is always the next one.