Of course this has happened 7 times before and will certainly happen in the future. I'm glad I didn't go into teaching ...
What you don't understand is that it will always happen in the future, as long as he is playing here ...
You need basics
Website's profit will always go up and down. By investing when profit is down, and divesting when it is low/down, you will always make more profit than staying invested through the process....
That's like saying "bitcoin price will be higher in the future, so it is always a good time to buy"....
Stupid, by buying low and selling high you can make profits.