That's a big problem in how most day traders view day trading. They think they "have to" or "need to" watch the markets all day to be a day trader. This is a misconception commonly among newbie day traders and other types of traders that are not day traders.
Those that figure out they don't need to trade all day as a day trader and can be successful at day trading just a few hours per day of trading. These are what I call the efficient traders because they know when to concentrate their trading efforts. Unfortunately, there are those that act as if they are offended by day traders that only trades part-time for a living (just a few hours per day)...they dismiss those traders via saying they aren't a true day trader as if their trading stats do not count.
Note: I have no real facts but I believe there are more part-time day traders making a substantial income from day trading while having another source of income (e.g. investments, job or business) in comparison to those that are exclusively doing day trading and nothing else.
Why day trade if its so tough ?
Some traders don't have the mentality or psychological make up to do swing trading or long term holds (position trading) while others have the psychological make up for day trading because they stress to much if they had to hold overnight trading positions especially in today's markets that are more globally connected than ever seen before in the history of the markets. There's also those that do many types of trading...day trade and swing trade and long term trading. They then label the trader as a guru, master trader, expert when in fact the trader never used such terms.
There's also a problem with how easy it is for a trader to open a trading account...only qualification is "some money" and "valid ID" and then you sign an agreement you understand the risks of trading but in reality...you do not understand the risks of trading. Then again, the same is true for other types of traders (e.g. swing trading, position trading) and investing.
With that said, the bigger problem with day trading as I've noted for +15 years is that most do not approach it as a business and most seem confused about the fact they can be a day trader (full-time or part-time) while holding another job or business...regardless if its passive income or primary income. Thus, I see too many day traders approaching their trading like a hobby while having the illusion it can be a job like any other job they've had.
As to the issue about day trading as a sole source of income...that's not really a retail conversation. Its more of a professional conversation in that someone that has the background of a professional trader or a strong network for such will most likely be someone that can do it...
Make day trading their only source of income because they understand the markets in a way that the typical retail day trader doesn't understand. Simply, there's different types of day traders out there that I prefer to view as the "professional day trader" versus the "retail day trader"...both are at home traders.
The first day trader I ever met was a former floor trader (he worked as such for 10 years) that had quit his job to trade his own account from home as a private trader. The second day trader I ever met was a former institutional trader (he worked as such for 12 years) that had quit his job to trade his own account from home as a private trader. After those two guys and for several years...then came the retail traders during the big boom of the dot.com days.
All of he above were at home traders. Yet, only a small group of them were very professional and business like along with having a professional network due to their prior background. Its obvious which group that was...the ones that refer to themselves as private traders instead of as a retail trader although both groups traded their own accounts.
That's my point, the typical retail trader that wants to succeed in day trading...you got to be more business like in your trading and if you need help in the beginning via having a job or business on the side...do it.
Therefore, day trading for a living is possible and some are doing it...a small percentage. They just don't have that typical retail trader mentality that you can do such while ignoring the business aspect of trading. There's another issue, the definition of day trading itself. Back in the 90's, it was very clear there were many types of day traders. Today, in error, too many folks believe scalping is the only type of day trader. In fact, scalpers are just a sub-group of several sub groups of day trading.
Scalping is tough. Only guys I know doing such successfully have a seat on the exchange that enables them to get special commission rates, using automation, using a broker execution platform suitable for scalping. Simply, I don't know any profitable manual scalpers that's been profitable beyond a few years but I do know a few that's been profitable for at least a year now...will be interesting to see if they can continue as such beyond a year.
Yep, they are newbies and trading all day as scalpers. These are the guys that will eventually burn out and/or they realize the financial burden of doing such for a living because life is very expensive especially if you got a family to support.
Last of all, I've seen some clever questions at the forum the past few months by folks asking if its possible to be a profitable trader or profitable retail trader that trades for a living without any other source of income with a small account...of course not. Seriously, what kind'uv stupid question is that. I've never heard of a trader with a 5k to 10k account or smaller being able to trade for a living...the cost of private medical/dental insurance, life insurance and paying other bills will eat up most of that 5k to 10k easily in one year alone.
Just as importantly, I've never seen anyone here at this forum say that a small account trader can trade for a living. Yet, I've seen many newbie traders ask if such is possible. In contrast, I've seen many here at this forum say a small account trader can be a profitable trader.
Too many traders are easily offended by someone that say they are profitable. They react negative as if someone is saying they are a billionaire, own islands, live in some multi-million dollar gated neighborhood and is a philanthropist.
P.S. Another way to look at the above long message...day trading for a living should be impossible for the typical retail trader that does not approach their trading in a professional/business like manner.