Most non-commercial stuff is done in camera though, and outside of commercial circles, adding blur in post is often frowned upon in the photography community. it's better to try and push yourself to get the best image you can in camera. You could have still tried to shoot the car with a slower shutter speed but taken the photo either in the shade or in the sun, trying to get the whole car lit right between such different lighting is very hard to do, an important part of photography is reading the light and working with it, it's something that takes time to learn though. The shot of the Skoda you easily could have gotten that level of motion in camera, the lighting is pretty even and you are pretty much parallel to the camera, panning does take practice but it looks so much better in camera than added in post.
@Mau, it's not a bad shot, but again too much dutch angle, I feel like I need to twist my head to look at the bike, and the composition is a little bit tight, the bike feels cramped into the corner, I also feel like the blacks need to be darker and it needs some contrast, it doesn't really pop in the image and just kinda blends in with the background and I'm not really sure where to look. That is another key thing, you need to make sure that the viewer is looking where you want them to in the image, so it needs to pop a lit bit compared to it's surroundings.
Edit: Just realised I haven't posted any of my stuff in this thread, so have a few random ones.