Yes holding bitcoin for long time is a very good way to earn more money but you should have that patience to hold your coins. normally people just keep spending their coins and trade a lot because they think they can earn more money in very less time. this is a problem with most of us.
yes and think it is also too much important to invest a good amount of money in long term investment. because you have to wait for a long time so it is important to get a good profit after waiting for such a long time which is only possible if you have invested a good amount of bitcoin for long term.