"Don't trade that timeframe, it's all noise. Trade XX timeframe or higher"
"Price action/S+R/Market profile/TA/indicators don't work, and you'll never be able to make any money from them"
"Vendors can't trade and should be banned" (followed months later by) "my new website is..."
"I'm starting a journal to teach you all how I trade/want to give something back (lol)" (followed months later by) "my new website is..."
"Discretional trading can't work" or "I don't know any successful traders who trade that way..."
"I'm still sure the system works but..." (After someone just blowing their account, or continually trading a losing system)
"The algos are making it impossible for me to profit"