
Professional investors normally make a good profit in stock market over a long period. The reason behind this, is, they have dedicated research analysts, they have knowledge to pick the right stocks and moreover, they stick to their own plans.
But this is not true for retail investors. Retail investors see the stock market as an option to 'Make some Quick Money'. Being a non-professional investor, they don't have a solid plan, no knowledge of stock picking and moreover totally dependant on market rumours.
But this is nothing but gambling. So, they face the same fate as most of the gamblers does - 'loose your wealth' in no time.