What were the best marketing learnings or advice you have been given?

Formally, I studied marketing, but honestly, that stuff from textbooks didn't help me at all. :D (sounds like wasting 5 years of my life, nwm)

The best marketing things I have learned weren't from courses, but through:
– own projects

– calls with someone better than me

– random social media posts or interviews on YouTube

The ones that stuck in my mind the most were:

• Find someone/product that is 10x better, copy that, add something of your own that is useful, and ship it.

• Show what you are doing (in short, be active), because if you don't show yourself, no one will know about you (my classmate said when I was starting yoga classes).

• Don't launch an affiliate program when you are starting. Launch it only when at least 50 people ask if your company has something like that. (We launched it when we had ~1 million downloads in the Play Store, but no one was interested. Now we have 9M, and people are already asking about it on their own.

What marketing learnings/advice were so impactful that you would welcome them in your business and life earlier?