"Get good at rational thinking" is a goal that's hard to measure progress, success or failure at.
With a business, you can measure stuff like sales, revenue, profit, widgets produced, number of widgets the factory throws out due to quality problems, number of late customer orders, price of raw materials required to build a widget, and much more. There are many things to attach numbers to. These measurements don't cover everything important but they help.
Websites can measure visitors per day, time on site, number of links clicked, number of visitors who return on a different day within 30 days, amount of people who sign up if shown marketing page A as opposed to signups for marketing page B, and much more. More intrusively and problematically, it's possible for software to e.g. monitor how much a user scrolls down on a web page and how long they spend with different parts of the page on screen.
But what do you measure when you're learning about rationality?
You can measure the time you spend on studying. You can measure words read and words written. You can measure whether you watched a list of videos and read a list of books. But those measurements don't tell you how well you understood the material. How effective was your learning? How much wiser and rational are you getting? It's hard to measure wisdom or rationality, or to measure anything very similar to them.
What's the solution? We must learn ways to think without measurement. We must get good at judging things in other ways besides measurement.
Measurement is useful and is something our culture is generally pretty good at. But it's certainly possible to think effectively in other ways. Measurement is resistant to bias, dishonesty and irrationality – it helps reduce those problems significantly – but it's not perfect at dealing with those problems and those problems can also be dealt with in other ways.