what is long term investment.

Hi all , I am really stumped at the moment and need help.

I am reading all over the threads how sophisticated investors are buying this and that , and then they are going to sell out soon after.

Isn't that what investing is all about?

I am a mid term investor , and expect to see a profit by 3 to 6 months or I know I have made a mistake and get out.

Sophisticated investors I also understand.

I just can't understand how long term investors think , they buy into a company that does not pay dividends , and then ... what?

Please , please enlighten me someone , I am totally mystified , and I am wondering if I am honestly missing something .

They are also the ones that pounce when a question is asked on a thread announcing they are in for the long haul , basically shutting down any discussion.

I understand , what I have just wrote , is a question and a comment , the question is what I seek an answer to, please.