If you are primarily a forehand attacker, many of your opponents will get used to your relentless forehand attacks, often from the backhand corner, especially after your serve. Why not throw them off with a backhand loop? This is especially effective against an opponent who routinely pushes your serve to your backhand corner. Surprise them - sometimes serve and get into a backhand position, and follow with a backhand loop! Too often players only backhand attack when they are caught off guard and they aren't able to use their forehand. Imagine how much more effective this is if you plan it, and have time to prepare. It means you don't have to step around (and, of course, many of us can't do that effectively anyway), you won't be out of position, and perhaps most important, your opponent has to adjust his timing to a different type of loop.
The key is to be ready both to backhand loop if the ball comes to your backhand side, or to forehand loop if the opponent surprises you by going to your forehand. If they do, simply rotate your waist to your forehand side and you're all set. But once in a backhand position, you can, if necessary, cover half or more of the table with your backhand loop.
You may worry that your backhand loop isn't as strong as your forehand loop, but if used as a variation, that's not only not a problem, it's a strength - the contrast will force the opponent to adjust. Not only will the backhand loop throw him off, but it'll make your no-longer-so-predictable forehand loops more effective. One of my best tournament wins ever came when, at 19-all in the third (back when games were to 21, best two out of three), after realizing the opponent had adjusted to my relentless forehand attacking, I serve and softly backhand looped twice in a row - and the opponent missed both.
As an addendum, if you are the reverse - someone who serve and backhand loops against pushes to the backhand - then you should do the reverse as a variation, and sometimes serve, step around, and forehand loop, just to mess up the opponent's timing. Be unpredictable!