sometimes they are not impatient but have needs in life that cannot be postponed. you have to believe that everyone believes that the price of bitcoin will continue to increase and bitcoin investment is very profitable but the necessities of life such as economic problems make them forced to sell bitcoin. I haven't found anyone selling bitcoins on the grounds that in the future bitcoins won't have a price, except FUD maker.
Yes exactly that lots of people are facing troubles in life due to their weak economic system therefore they sell their bitcoin so because of this it is necessary to invest little amount but that amount which you don't have need for everyday life. Although future is unpredictable no one has any idea that what will be their economic status in future but one should think and plan for the future.
Certain rules should be follow for the future because if without planning you enter to certain field then success become difficult in that field. If there is no other way to cover the uses then selling bitcoin is not a bad idea because people make investment to be used for future.