Originally Posted by moby
Exactly. It's very difficult to run around the backhand the same way as the forehand. The forehand is a more dynamic and linear shot with a naturally bigger strike zone, and one that you can skip around and make a lot of adjustments with even as you are preparing your stroke. On the other hand the backhand requires more stability, and in particular, the double handed backhand is more of a rotational shot and so requires the feet to be set for optimal hitting. As for the one handed backhand, because the stroke requires a large relaxed swing with a lot of room, and the nature of the inside-out stroke is that the ball comes into your body and tends to jam it a little, this makes the already difficult timing even more difficult. It's not surprising that the 1HBH on-the-run out wide is the easiest 1HBH shot for most people to execute, from pros to amateurs.
I was just going to say that as a rule it's better to be a FH than a BH player since a FH is easier to bring to bear as the footwork required to hit a BH is more complex and much less forgiving of last-minute adjustments in positioning, but in the above paragraph you'll find a much more detailed explanation of this. Bolded part is a very well made and very important point.