Generally a watch is supposed to fit on your wrist "properly" if you can get one finger between the band and your wrist. I never liked watches that had to be worn very tightly - or even less when people wear them like bracelets and they basically keep swinging around the wrist.
With the Watch, you have to play with it - too loose and it will lose contact with your wrist and either not make readings properly and in some cases it will think it was take off and lock itself; too tightly and your fingers will turn blue! When I first got my Watch - I only had the Black Sports Band at the time - I had to go to the Apple Store to purchase Apple Care and the guy who was helping me (after getting over his jealousy that I got mine already and he didn't) asked how I liked it, and I mentioned that I was missing the tapping. He felt that I was wearing it too tightly. The way I took the picture with the Loop band is probably pretty close to the way I wear it with the SB.
The pic on the right looks as if you skin is bunched. That is why I ask.
On my SG Sport (42mm) I use the shorter band. For everyday I wear it on the 2nd notch, but when I work out I tighten to the 3rd.
I don't find the Sport band particularly comfortable (fine for workout). I also don't really like the looks w/the SG Watch. I have adapters and other bands on order.