1. Saying "Hi" to a co-worker you run into on the way to work
You're going to be in the same area as they are ALL DAY. If you guys really have anything to talk about, I'm sure you'll do it by the watercooler or wherever people with real jobs talk about stuff. For now, just let them finish up their podcast or listen to whatever's on Pandora.
2. Holding the door for someone who's more than 6 feet away
If you see someone over 6 feet away, just don't hold the door for them. Seriously. They're not asking you to do it, and it's gonna force them to hurry up so they don't feel bad. Everyone walks away from that situation wishing you woulda just walked in and let the door slam behind you.
3. Stopping your car and waving a pedestrian across when you have the right of way
Listen, we set up the traffic rules for a reason: so stuff like "politeness" wouldn't be a factor at a 4-way stop. But when it comes to crosswalks, just follow the lights - a pedestrian looks like they wanna walk across the street, but you - the person in a car who has a green light - is letting them walk past? You're going to confuse them, they're not gonna walk immediately (if at all), and you're going to piss off everyone behind you.
4. Recommending a TV show
Since TV shows mysteriously got REALLY good sometime in late 2004, everyone's got a show to recommend (and it's always The Wire). But here's the thing - most people have access to a lot of streaming outlets that have ungodly amounts of TV shows on them, and their backlog is already bad enough. Don't pressure me to watch The Americans! I'm still catching up on Friday Night Lights and The Shield. I don't need to feel guilty about not watching ANOTHER powerful, immersive, hourlong drama. If I want a TV show recommendation, I'll do what any normal person does: ignore that impulse and watch a bunch of reruns of American Dad.
5. Suggesting appetizers when out to dinner with friends
Listen - it's going to overcomplicate the bill, no one's going to feel like they got enough, at least 40% of the people at the table will wish a different appetizer was chosen, and everyone's gonna walk away a little bit pissed off about it.
6. Leaving a voicemail
If you call someone and they don't answer, here are your options: if it's important, text them (saves time, allows them to get the information quickly, and you can include fun emojis); if it's not important, don't leave a voicemail or text - they'll see they have a missed call and call you back. And that's it! There's absolutely no scenario when it's better to leave a voicemail - which forces the other person to listen to the stupid opening voicemail voice telling you that you have a voicemail (which - of COURSE I do, I already knew that, that's why I'm listening to this!) and usually ends up just being "call me back."
7. Getting a birthday gift for an acquaintance
Maybe you think you're being nice by getting a birthday gift for someone you don't even know that well, but you're not - you're making things worse for everyone. Now THEY have to feel guilty that they didn't buy YOU a present for YOUR birthday (and for not even knowing when your birthday was), they have to write you a thank you card, AND they have to pretend to like some gift that they probably didn't want to begin with (if you don't know a person super well, odds are you're not going to know what kind of gift they really want).
8. Saying "Whatever you want" when asked what you want to eat for dinner
Listen, you're not helping anyone, and saying you don't care is a goddamn lie - EVERYONE cares at least a little bit. There's always going to be at least ONE thing you don't feel like eating, so contribute to this decision in some way.