Most people like pictures of people. But the general perception is that most people don’t want their picture being taken. The result is that many photographers start shooting snapshots, without their objects’ consent or knowledge. Although this can work out fine every now and then, in my opinion this approach usually ends up with bad results. I’m talking about the messy images from crowded markets, with tilted horizons and all sorts of crap in the foreground. And even worse, when people discover what’s happening, there is a good chance that they will be angry.
In my experience, most people don’t mind having their picture taken at all, many of them actually like it! I think it all comes down to the way you ask. If people feel that you have a genuine interest in them, the chance that they refuse is very small (and if they do so – that’s not terrible either).
It does help if people can see (and feel) that you know what you’re doing. That’s why it may be a good idea to adjust all your settings (shutter, aperture) before you start the conversation. Even more so if the light conditions are challenging, as was the case in the image below. I took the shot in a small shop in NW Namibia. While I bought some groceries I noticed the man and his grandson, sitting next to the entrance. I chatted a little with them, grabbed a camera from the car, took a few images of the shop to get the exact settings I'd need and then took this shot in only 10 or 20 seconds.