If your business plan is selling software to people, 98% is not plenty at all.
If your web app crashes one out of every fifty times I launch it, it's not good. The business side of things is reasonable to prioritize right up until it isn't.
> If your web app crashes one out of every fifty times I launch it,
If you're using a different, random browser every time you access our web app, you're in a minority far smaller than 2%. Or you've shared your account with 50 friends, and we'd prefer that you do that with someone else's app anyway.
If your web app crashes one out of every fifty times I launch it, it's not good. The business side of things is reasonable to prioritize right up until it isn't.