one year is enough for us to hold our Bitcoin. You can sell it and start another holding process by buying Bitcoin when the price is cheap. Many people have succeeded with this way and I doubt that you can fail. Only hold Bitcoin in more than 5 years when you have a good capital.
Let's say you bought 1 BTC last january 2014, you would have paid around 620. One year after, your BTC dropped to less than 200, not a good deal !
In 2014 everybody knew bitcoin was going to go down all year, sorry but those who bought at 600+ in 2014 needed to do more research or hear their feelings before purchasing... even at 400 usd it looked still expensive to me.