The other reason why countries don't want to self-identify is they become a lightning rod for political attention and negative attention from the brand-name pharmaceutical industry.
Recently in Thailand, with a drug called Aluvia, an anti-AIDS medicine, the Thai government said it was going to issue a compulsory licence to import the product from India. Abbott, the owner of that patented product, threatened to pull seven other products off the market and put tremendous pressure on that country. Eventually, because of pressure from a lot of the NGOs and political pressure, Abbott backed off and is now making the product available at lower prices. However, without an effective functioning compulsory licensing system and without the threat of generic competition and lower prices, that would never happen.
Countries don't want to self-identify because right now they don't see an effective regime, and it's very difficult for them.