What bugs you the most about validating an idea?

I have launched about 6 apps now with not much luck.
Now im a lot more careful with my ideas before jumping in and building a MVP
I find myself building new landing pages that all follow the same structure

1. Build a landing page
2. Add some kind of funnel
3. Drive traffic and see if theres any interest

Curious if people find themselves doing the same thing. Or if they have figured out how to validate ideas another way or a really fast way to complete those 3 steps I listed above?

Any advice is greatly appreciated
Thanks!