I recently read that, to be a successful large-scale short seller, you have to be an activist.

You can't just sell a stock and wait passively for it to eventually go down. You HAVE to be out on CNBC and elsewhere trying to actively prove that the company is overvalued.

Look at the way Bill Ackman and Pershing Square Ventures went after Herbalife for years. Not (just) because they thought a fraud was going on. But they were trying to make billions of dollars for themselves too.

https://www.nytimes.com/2018/02/28/business/dealbook/ackman-...

Ackman spent 5 years on the road doing roadshows, on TV, trying to make the case for fraud.