Certain standards and minimums undoubtedly are rigorously implemented and enforced, and I am sure their application depends on the type of visa. But uniformity can fly out the window. On the individual level, some visa officers like pictures, others emphasize financial ties to the host country and thus a mass of documents, though they may not understand them. Most I am sure are extremely suspicious of lying and some perhaps are having a bad day. So, perhaps like everythign else, the human element once again enters and can affect the outcome of a visa application. On a general level, also coming as somewhat of a surprise, is that different consulates in one country could have different procedures or standards from others in that same country, maybe different leniencies or less/more emphasis on certain factors (apprarently there is not much communication between them to standardize uniformity, each consulate with a different ambassador with different whims, dispositions, goals, ambitions, etc. and each consulate rotating visa officers about every two years), making the chances of approval that much more obscure and unpredictable. The vagaries are frustrating and that is one part (and a small one at that) of an immigration lawyer's job: to understand the differences between unspoken consulate policies in order to offer the best chances of maximizing the success of clients. I just find it amusing how there could be such significant differences, thus perhaps giving the whims of an individual more power than the organization. Nevertheless, I should disclaim that the fundamental standards enforced by all of them do ensure some uniformity, however negligible they might be.