The second one looks wrong for the following reason:
- in order to render the lane line horizontal, you need to be pointing your camera directly across the pool, at right angles to the side. It can point up or down or horizontal, but it must point at right angles to the side.
- the view on the swimmer in #2 makes it clear that you are NOT pointed directly across the pool in this fashion
- therefore you must be tilting the camera
In #1 the angle of the lane lines across the frame is consistent with the view of the swimmer, you appear to be holding the camera level, and pointing it back down the lane toward the swimmer, you are facing diagonally across the pool.
Don't be fooled by simple lines -- the mind is pretty sophisticated at putting together visual cues to see what's going on, and if the camera was actually level, there's an excellent chance that the picture will "look" level, no matter what's going on in it.
Agree that the purple bunting is distracting. If it was slightly sharper, it would be a nice element, but since it takes a moment to recognize it, it's just a distraction.