I looked at your match history, I noticed you play a lot of darius.
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Flash. Flash is one of those mush have summoner spells, you'll notice everyone has flash. (Unless they're on a champion that doesn't need flash and other summoners could be used better) Most people keep flash in their D.
Darius being a top laner you got 2 good choices for a second summoner spell. teleport or ignite. (Your prefrence)
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I notice you follow the same build every single time. I was always told this is bad. Things happen in league, you can't just build the same things over and over and hope you do good so you can snowball. Sometimes you don't do so well and your set further behind because your trying to finish your OP build but you dont have the money or the items you should have at this time.
this is where situation items come into play. Alot of people build bork or trinity force on gnar first, sure Ill build trinity force when im against a tank because that shreds tanks, but if im going up against someone whos a very bursty AP lets say.. a vlad.. I'll want some AD and some MR so I build maw of malicious. 
When I play ADC, If im doing good and have 50+ CS and or a kill by 10 minutes in, I will build Infinity edge. But If they get a kill on me or im lacking CS, I go Blade of the ruined king for the attack speed and sustain. and a nice active.
everything has its reason to be build at a certain point in the game.
use this video - https://www.youtube.com/watch?v=ufTaJzATTz0