Testing assumptions is at the core of every successful business. The best companies are always experimenting and trying to find something called "product market fit."
Product Market Fit is when you find a use case for your product that really makes sense and solves a real, tangible need.
It can be really hard to find PMF for a few reasons:
Largely -> You do not know what your consumers think. You have your own opinions but it can often be challenging to estimate user perception.
SOLUTION: Build feedback into your product. AKA use surveys, get on lots of phone calls and try to figure out how your product "Fits" in to your users' lives.
Get one user. Then two. And find the intersection of those two users answers. Then 3. Four. And so on.
The key is to move really fast and throw out your own bias. Let your users do the talking.