Watching session replays made me realize my users don't behave like I expected

Running a small fintech app, around 3k users. Thought I understood our user journey pretty well since I built the whole thing and talked to users regularly.

Started looking at actual usage patterns last month and realized I was totally wrong. I designed it thinking people would go Settings > Link Bank > Start Tracking. Made sense to me, logical flow, good UX.

Turns out 70% of users open the app, tap around randomly for 30 seconds trying to figure out where to start, then either stumble into the right flow by accident or just close the app.

The "getting started" guide is there but it's hidden in a dropdown menu that apparently nobody clicks. People want to just start doing the thing, not read instructions.

Now I'm redesigning the whole onboarding to match how people actually behave instead of how I thought they should behave. Feels obvious in retrospect but I genuinely had no idea until I saw it happening over and over.

Anyone else have moments where you realized your mental model of user behavior was completely off?