Once you get to the point where you can remember to take the lens cap off, load film or a memory card into the camera, and remember to push the shutter button when things look interesting through the viewfinder or LCD, you are finished with being dumb, right?
Not really. Everybody has a bad day. Here are some that I've encountered.
Some of my worst shots I thought were awesome while I was taking them. Because I figured I was Ken, God Of The Camera and I knew what I was doing. So I was really excited about waiting for them to come back.
And, as it turns out, most of them sucked. My exposure was totally off.
If you get cocky, you will stop double checking things and you'll work at a faster rate. It's almost a guarantee that you are going to screw things up.
If somebody tells you to never use Photoshop, they are an idiot.
Photoshop (and Gimp and Paint Shop Pro and others) are powerful tools. To deny yourself a powerful tool is inhuman. Tools are a sign of intelligence that humans have been using for a long time.
But it's usually faster to spend a few minutes to sweep up the crap off of the floor, get your lighting close to right, and meter and compose carefully than it is to spend hours tweaking an image in Photoshop.
The one I'm most guilty of is taking foodporn pictures in my kitchen before I've cleaned up the mess from cooking. I'll have already eaten the foodporn item (Hey! I'm hungry!) and then I'll realize that they are all out of focus and look like crap.
Usually the lack of care you show by figuring you'll fix it up in Photoshop is infectious and you'll find that you aren't taking good pictures at all. And fixing my screwups really destroys my enjoyment of the process. Just because you can fix blown out highlights doesn't mean you should count on it.
Without fail, the first few shots you take with a new piece of equipment aren't going to be that good until you get used to it. And you really want to make sure that you are certain that everything actually works before you go, while you can still return it.
If you are going to buy a camera before a vacation, buy it a month or two ahead of time, so that you can get used to it.
You might discover that you are missing an important part or that it doesn't quite work right with your gear.
There's a common set of gripes that photographers who shoot women have. The model wants to have her boyfriend or best male buddy handy. And sometimes, there are stories of the boyfriend holding reflectors, moving lights, and whatnot.
But sometimes the boyfriend just saps the energy out of the shoot.
It doesn't need to involve models, but this is the most popular example. Maybe you've got another photographer who is just taking the same shots you are but 30 seconds after you do. Maybe somebody's looking at your LCD and offering you unhelpful commentary. Maybe they are just not your type. They can kill the mood.
This is worst when others are expecting results from you. If I go for a walk and don't take any good pictures, it's no biggie. But if I shoot with a model, she's going to expect to see sexy pictures back.
If you are thinking too much about there being a hot woman in front of your camera and not enough about the basics of photography, you should stick to landscapes. If you are a wedding photographer, the bar is off-limits. If you are pissed off about something, you need to figure out how to calm down before you go shooting.
Macho photographers shoot in manual focus, manual exposure mode, with prime lenses, and only with a macho-photographer's camera.
This is a great way to get in trouble.
For example, I saw the results when a wedding photographer was so macho she shot the whole thing in manual mode... but there were patch clouds overhead that kept screwing up her exposure, so half of them were underexposed and the other half were overexposed.
You can obsess about fancy cameras all you want, but the simple truth of the matter is that I can fit my Canon G7 in my pocket easily and you can't fit your Hasselblad in your pocket. Sometimes what really matters is just being there.
The simple truth is that in highly chaotic situations, you really don't have any brain power to spare. So sure in the old days, people were able to shoot sports without autofocus, but these days, you'll probably get better shots with autofocus and without manual exposure. Same thing goes for weddings and advanced flash functionality.
Photography, you see, is about what's in your head more than raw technique. But that's normal. Tennis is about far more than getting the racket reliably in front of the ball and cycling is about far more than moving your pedals in a circular fashion.