For many years we have understood that choice and control are imperative to the welfare of all living organisms. However, once this phenomenon was discovered, it was assumed that if choice is good, then more choice would be even better!
Many human studies have proven this to be incorrect. Indeed, too much choice may lead to ambivalence, frustration, confusion, anxiety, stress, drained psychological energy and reduction in self-regulation. Although this seems counter-intuitive, the phenomenon can be observed in even the most basic of marketing experiments.
When researchers open a mini-shop offering over 20 flavors of a particular product, and then close and re-open offering less than 10 flavors, the shop with less choice will sell far more product overall. Having greater choice, does not result in improved decision making; rather, reducing choice can be seen to facilitate the process of decision making and, in many studies, has been linked to a reduction in associated stress.
Some of the reasons for this are quite specific to humans, as we are able to feel ongoing regret for a perceived poor choice, and we have the capacity to continue to compare our selection to all of the choices we didn't select.
However, there are also some underlying principles that can easily be applied to our dogs. If we offer only a very limited number of choices in a given circumstance, then the decision process is less difficult, is likely to be made more quickly, with less frustration and/or ambivalence, and the "right" outcome is far more likely to be selected. We know this. We implement this in many of our training strategies. We set the dogs up for success. We limit the other options available (e.g., the item we want the dog to interact with is the only item in the training environment initially). Then of course in conjunction with this strategy we heavily reinforce the behavior we desire.