First thing is define what 'consistently' profitable means to you. consistently profitable every trade? or consistently profitable every day? or consistently profitable every month? or consistently profitable every year? Let's say consistently profitable means 95% probability of a winning month. To be consistently profitable like that, you probably need to find and take well over 100 positive expectancy trades every month. Taking just 10 trades a month would not be enough to have 95% probability of having a winning month. It would might be more like 66% which might not be enough to be considered as being consistent.
HE maybe right\ if we take out 1987. Assume you count actual trades, not all the fake data; + dont count 1987. Sure could be priced wrong[ too expensive] consistently. Same way/ a real estate derivative [mortgage]could be priced expensive, but consitently profitable. [But take out 2022 RE prices + for sure dont skip appraisals or BPO\LOL] FSB0[for sale by owner] are almost ALWAYS priced too hiGH consistently....
%% Good points s-trader; + depends on the business. Service businesses, 5, all 5 profitable from 1st week. But 1 week doesnt mean much. Trading- investing public markets\ i did so non random\terrible 1st year ; i figured i could do much better than average\LOL [Skip my loss-service business in Argentina loss; a different nation = too different, but that was my fault , +no Mark D psycho-babble helped.] Jack Schwager top trader Books helped Sounds like you will be profitable ,s trader ; +no offence to any one , but the pro or industry standard is months %+ years%. That's personal with me ,noting weeks profit