This is very true. So, doesn't it stand to logic that making random entries would work?
surf
I'm sorry, I overlooked your reply. I am in limited agreement. If you limit that question to whether you should buy or sell, I believe you are correct, and Peter Brandt said it best. Brandt, who has averaged around a 46% return for decades with a max drawdown of 8%, says that a trader could have made a very comfortable living taking the other side of his trades. By this he means predictions are a small part of the picture, primarily because you are on the right side half the time just by chance.
The decision to buy or sell is the easy part. I think the much more difficult side of the business is timing your trades. Entry/exit placement are definitely something that cannot be done randomly.
The final component is having a process that keeps your human instinct out of trouble spots where you can assume you won't follow your rules.
I think that most traders spend 90% of their time trying to get on the right side of the trade and 10% on everything else, when in fact the business works the other way around, opinions are easy to come by, timing, money management, and psychology are not.