Persistence is the key. Lots of people today are very good in starting anything, but are not good in finishing them. At the beginning they are so fueled to over and over again what they have started. But when trial comes their excitement are gone. It is nowhere to find. 

Persistence is the key to success. If you don't persevere, no matter how good and skillful you are, you will never still succeed. Persistence is the key because it will unlock next opportunity of success. Quitting is not the option for the victorious people. Though they stumble along the way, but they never chose to surrender. They may set back for a while, when needed, but they take those moments as opportunity to plan for the better move so that the next time they encounter the same problem they will have already an edge on to handle them.