The most profitable bitcoins I ever mined, were the ones I mined when it was unprofitable to do so.
Yup. Bitcoin back then was unheard of by many people until the ath back in 2013. Most people jumped into the train thinking that they could get some easy money out of bitcoin. But look at those who invested during that time. They are now worrying because of the massive price drop.
Sort of like what is happening now because bitcoin reached an ath last December 2017. Now, those who jumped on the train are getting off because of how low the price went. Those who stayed and continue to stay will profit even more because they were able to buy or mine coins. Many get discouraged easily when they dont profit immediately and get envious of those who were able to do so but it really takes hard work. Theres no easy way to get rich, there are no short cuts definitely not in bitcoin.