Technically speaking. This depends on the type of trader that you are. For swing/trend trading it may take longer for one to become a moderately successful trader.
Now, that is not to say that there are some people that are gifted when it comes to trading, and hence it may take less time to become successful.
Their is a going rate in the industry that you should have 5000+ hours under your belt before you can say that you are proficient. I disagree with this. It can take more or less time depending on the type of trader you are.
Lets take for example, you are a technical trader, you use technical tools to trade the markets. It is your sole and only way that you trade the markets. You have some success and some failure but you use the technicals to your advantage and you start to learn from your mistakes.
Now lets say you are a fundamental trader, you use the news of the world to get a bigger picture of what is happening (mostly swing and trend trading happens in this area). This is an easier time and takes far less to grasp an understanding of what is happening.
Now combine the two. what do you get?You get the fundamentals which gives you the ability to know that the market should start moving in a single directions, couple that with the technicals such as fib lines, support resistance and volume and you can start seeing areas where the market will move to and where it will continue.
This takes far less time to accomplish and can be learned relatively quickly. Most traders will go for the quick, purchase this EA, let it trade, opps blew up my account, lets buy another, blew up account, etc scenario.
However, EA's are missing a fundamental reality. If you don't know where the market is going to go, how can you ideally have a successful trading scenario?
Ultimately, my experience is that it took me a year to get out of the new trading experience. Now when I look at the overall view. It is a clear picture and I don't worry about the market making sudden movements.
Let me know if you have questions, I can go on and on about this....
Hope this helps.
I do not follow the path of others, I create my own path and leave a trail behind me