My local shelter accepts volunteers to walk the dogs. However they limit each walk to a maximum of 20 minutes.
I'm a bit puzzled by this limitation. Considering that shelter dogs generally live in a very stressful environment I think that this policy is quite bad for the dog: the dog experiences even more stress when getting ready for a walk as he knows it's going to be short. Even with no prior experience, imagine this: the dog is already under stress. He meets new people. He goes for a walk. After 10 minutes he has to turn back and go back to the shelter.
People walking a dog in view of adopting him will have no chance to see the dog in a "normal" state of excitement or stress.
Their argument is that this gives more chances to the dogs to be adopted: the dog can't be adopted if he's not in the shelter.
Are there studies about shelter dog adoption considering this problem? Or other sources suggesting that this could be beneficial/detrimental to the dog?