Double Subverted: Bob buffs up in a Training Montage and becomes more assertive as the story goes on. By the end of the story, he's a Badass worthy of his trenchcoat.
Parodied: Bob always speaks in a gravelly voice, he's covered in tattoos, and he always has five o'clock shadow. A kid tries to steal his trenchcoat, believing that it will make him a Badass as well.
Zig-Zagged: Bob has a rotating wardrobe, and he only wears a trenchcoat from time to time.
Averted: Bob is a Badass, but he refuses to wear a trenchcoat because he believes it will slow him down in a fight.
Enforced: Bob wears a trenchcoat because his action figure will sell better than his normal outfit.
Lampshaded: "Of course I'm wearing a trenchcoat. What kind of a Badass would I be without one?"
Invoked: Bob is just starting out his career as a bounty hunter. The first thing he does is buy a trenchcoat, believing that it's mandatory for all Badasses.
Exploited: Bob is starting out his career as a bounty hunter. He buys a trenchcoat because he knows that people consider them to be badass and wearing one will help his image.
Defied: Bob is a normal, well-adjusted guy who wears a trenchcoat because he thinks it looks good on him. When people assume that he's a "bad boy", he just rolls his eyes.
Discussed: "Who does Bob think he is? Idiot...it's a coat, not an 'Instant Badass' recipe."
Conversed: "Man, I wish I had a coat like that...nobody would fuck with me."
Bob is a traumatized war veteran with a criminal past. He wears a trenchcoat to hide his scars.
Bob's coat may look cool, but it may also be slightly cumbersome, get caught on anything sharp that sticks out (or get sucked into a jet turbine), and if nothing else it may make the wearer feel too warm if worn in a hot environment.
Bob is a brave, good-hearted detective. He admits that he wears a trenchcoat because it gives him confidence.
Bob gets a coat that is lighter and tears easily, thus keeping his image badass and dealing with some of the practicality issues.
Played For Laughs: Whenever Bob puts on his trenchcoat, "Bad to the Bone" starts playing in the background, and everybody stops what they're doing and just stares.