Most day traders lose their money in 3 years

I was talking to a friend who has been an investor for around 30 years. He said he had once been a day trader but realized that one tends to lose sleep because of all the continuous gambles day after day. This loss of sleep makes one slowly lose their good judgment. So my friend told me the apparently little known fact that 95% of day traders tend to lose all or most of their money within 3 years.

I suppose a way to avoid this might be to day trade for a few weeks, then do something else for a few months and then do day trading when you are feeling and thinking really sharp again without any real problems that you are dealing with. That way if you start to lose sleep over investments, you become aware of it and just stop day trading for awhile.

I talked to another friend that said he had stayed at day trading too long and he eventually lost all or most of his money. He is in another profession now.