I don't believe reaching 100% crit is a good idea. Instead, I would improve my damage or my survivability. First of all, when you build a champion, you should consider who are you against. Static builds are terrible, your build should adapt to each game depending on who are you against and how is the lane going.
Anyway, if we talk about END GAME build, consider items that are a MUST for an ad assassin:
Infinity Edge, Last Wisper.
You already have 40% crit, and your crit deals 250% damage. You can now get a Static Shiv or a Youmuu's Ghostblade, reaching 80% crit with a Static or 70% with a Youmuu ONLY WITH ITEMS + PASSIVE.
At this point I would stop building crit, and I wouldn't also wasting runes slot to increase it, instead I prefer scaling damage or armor penetration runes. Yes, yasuo passive is OP, but you should consider that reaching 100% crit is pointless because you should consider your average damage output and improving your attack speed and / or damage is more rewarding.
At this point you should have:
Infinity, LW, Boots and Static.
You should get one defensive item (GA is usually preferred) or Mercurial Scimitar (nice if they have strong CC, but has also noticeable damage) and if you like life steal Blade of the Ruined King or Ravenous Hydra.
Final Build:
Infinity, LW, Boots (attack speed), Static, Ravenous Hydra and GA.
Now you have:
+195 dmg
+80% crit
+12% life steal
+65% attack speed
+35% armor ignore
+6% speed
+50 armor
+50 magic resistance