Exactly. If you devout full time in trading like 8 hours per day or more then you can generate income but not pegged at certain amount. You can even a whole month income for just 1 day in trading. The point is your willingness to fulfill it as fulltime job then consider yourself making a living by trading in BTC.
It's useless to spend even 24 hours in trading if the price is not much moving. You can't also applied that to a certain altcoin in terms of altcoin trading.
That is not a wise way to deal with trading just to have a fixed income so a big no for doing that kind of thing. Fixed income means that you will receive a designated amount in fixed period of time which is not possible in cryptocurrencies' big price volatility. You can earned big in one shot that can covered your earnings for the next following weeks or even months but same goes that you can also lose in a single shot.
that is true and i am really agree with chaser15 said, better we doing another thing that will be useful for us than only trading for 24 hours and beside that, its not good for our healthy. i think we can spend in every 4 hours only to watch the market and we can make analyze with the conditions from the market then we can decide what we want to do.
You can choose daily trading instead of choosing minute or hourly trading. since its not easy to make profit in trading but if you know the movement or how to analyze then you are in the right place to make a good profit..
If you have a large capital you can make a good more profit than going to small earnings.