Looking too far ahead

it is a mistake to look too far ahead, the chain of destiny can only be grasped one link at a time by Winston Churchill. .. guys.. what do you think about the quotation? i think it's kind of true.. because i always plan ahead .. and.. most of my plan don't seem to work.. i plan few years ahead.. and i end up differently.. why is that so? how can i stick to my plans? do i need more dicipline? i always studied hard and plan for my future.. i don't wish to end up in poverty.. nor in middle age class type of person.. so i work extra harder.. i know that's the only way to success.. but.. am i doing the right thing? i don't enjoy myself like other teenager does.. i feel like i'm losing my teenhood at times.. is this true? do i have to enjoy myself or should i be planning for my future instead?