Never Be a Programmer in a Suit
thecodist.com
thecodist.com
However, a suit (or the lack of one) can affect how people think of you. Its always good to be aware of your choices and how they affect other's perceptions.
One other comment, as far as the suit thing goes, It can look very different, depending on what look you are trying to go for.Do you look like a famous actor between movies? A rockstar? A Houston oil mogul? English professor? Southern gentleman? Mafia hit man?
Personally, I like suits and some formal elements mixed in with casual stuff, too. But I'm also an artist, with blue eyes and long blonde hair and can pull off a movie star look. T-shirts and crappy jeans are ok, too, but I got tired of looking like a college student. Personally, I like looking good. And, to be totally honest, I get a lot of compliments and I like the additional attention from women.
Also, sometimes it's appropriate to go for sameness. Suits are goid at formal events. Weddings and funerals, for example.
So... if everyone is wearing jeans and a sweater (like in my office currently) you'll stand out with a suit?
Nope! If computers worked better when the programmers were splendidly dressed, that would make splendid dressing an effective tool.
Alas, programmers, by and large, don't like those; they prefer working with crude tools, or none at all.
They would say, things like, "Real programmers can proudly make it work without the cop-out of just putting on that Armani. Debugging with Armani is no more effective than a well-placed printf if you know what you're doing."
Baggy pants and a baggy t-shirt look horrible but you won't stand out in a room of programmers. A poor fitting suit will stand-out in the worst possible way--it'll look horrible aesthetically and reflect either neediness, incompetence, naivety, or some combination thereof.
If I had the money I'd wear a tailored suit every day. Not because I want to look flashy, but because I know dressing well matters[1], and because I'd love to be one of those guys with a closet of nearly identical suit "uniforms" that would remove all choice from dressing in the morning. Plus I'd have to professionally launder everything, so much less laundry. You can do something similar with denims and a casual shirt, but for various reasons that can be a trickier proposition, albeit much less costly.
[1] It's near impossible to come across poorly in a well-fitting, single-breasted, conservative suit. But fall short of well-fitting and you subject yourself to ruthless scrutiny.
[2] The conservative suit works well in almost any business-related environment--again, zero decision making required in the morning--whereas a Silicon Valley uniform would never fly in NYC, DC[3], a court room, etc, and IMO is more likely to come across as more pretentious than a suit in some environments, as denim+polo or similar attire can suggest bro culture, frat culture, etc.
[3] Yes, plenty of technical people in DC and even NYC adhere to a California business casual aesthetic, but the people with power or money almost universally look down on those people. In California that same kind of calculus is rarely so simplistic, but in any event on neither coast can you go wrong in a good, conservative suit.
You can be a good programmer in or out of a suit. I just did a Google image search for Vint Cerf, and didn't find any pictures of him in anything other than a suit.
Keep it simple and easy to change.