There are many investors who suggest that you focus only on buying. Everyone may have said this from his own experience because the more we increase our investment the more likely we are to earn a profit from that investment. It is not the case that a person can profit only by investing. 

After investing money can be lost and money can be increased but this risk of money has to be taken by investors if investors want to gain profit in future. It may be difficult to hold the investment for a long time and maintain the consistency of the investment but the road to success is not easy it is always difficult so everyone has to accept it.