Keep on going, and the chances are that you will stumble on something, perhaps when you are least expecting it. I never heard of anyone ever stumbling on something sitting down." Charles F. Kettering
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You may never know where the greatest opportunity that will bring a turn around in your life will come from and that's why you must keep going.
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Don't let discouragements, disappointment diswayed you from where you are going, just keep going. It will seem like the road will lead to no where but just be focused, keep going, keep trying and keep working.
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Great inventors who have changed our world and have made significant impact started a journey of achieving their dreams on a path which looks blake and unrealistic. They tried working on their ideas and encountered a number of failures yet they never stop them till they finally brought forth their best.
What you least expect always happens the moment you begin something but not when you are idle. Every move and action you take counts so get up and begin something.