It's obviously a case of a guy who wasn't able to make it. Most aren't. In any business - by the way. There's a universe of evidence against the efficient market hypothesis. He seems to imply that because he didn't make it - maybe it's impossible. That's where he goes wrong - but the reason for such statements is simply to minimize the psychological pain of failure and to de-personalize it away from himself.
Both good points. What immediately occurred to me was that his partners didn't give him their winning strategies for whatever reason. Either they didn't trust him or they just wanted to get rid of him.
It can also be the worst advice anyone can give, depending on the specific case. Unless you mean "don't give up (on yourself), but you might want to give up on trading and try someting else". The markets are changing and if anything getting more competitive. That's not to say he shouldn't continue trying, but there's also a sensible point at which to quit one thing and move on to something else. It's up to him to discern that, however difficult it may be. Everone's time is valuable -- and there are certainly other satisfying ways to spend one's time/effort aside from trading.
Why you quit algorithmic trading? Simple, your algorithm sucked. Could we at least introduce a little honesty into some of these discussions.
to the poster: 1. the market changes, there is no 1 single strategy that can do all the market! 2. historically test your strategy, and know that no strategy lasts forever, one day it will break... so Diversify! 3. using algo trading is not like paper,limit fills are not guaranteed, and stop fills might be away from the market! so if you work in a short time frame period, think twice... 4. i dono what is the percentage , but a big percentage of the market is computer trading algos! good luck