No, it's not perfect, but it might be the only chance you get to record the moment. Pictures are About Memories Not Photo Contests.
Some of you are really serious amateur and even professional photographers, and some of you are just people trying their best with a camera to get good pictures and to record those once in a lifetime memories. I wish I were a professional or even amateur photographer, but what I do know is that for most of us the heart of the photograph is to give our travel moments a little version of eternal life. We are changed when we travel; our heats beat in a different land, and they begin to synchronize with the people around us who are so different from us but are suddenly, startingly, so much like us. Just as Thomas Wolfe said, "You Can't Go Home Again," you can't really entirely keep those travel moments no matter how hard you try. The photograph is about the closest you are going to come to reliving those stunning moments when you understood the world, and, hence, yourself, better.
When the only chance you have to take a picture is out the window of a car, go for it. When I was driving five hours North of Addis in Ethiopia, I saw the most incredible vignettes out the window of the car. I knew a lot of them would never come out at all, and a lot of them are little more than blurry pictures of the sideview mirror or windshield, but I had to try. In these blessed days of digital images, you can afford to just point and point and point and shoot and shoot and shoot. I know the other people in the car, eight of the ten were Ethiopians, thought I was crazy to even try, but, see, even if a lot of them did not come out, some of them did. Some of them did and those pictures do help me to keep those travel moments. A picture doesn't have to be perfect to be valuable.