They are not doing a statistical determination. There is no algorithm behind it that indicates when a country is safe to do business with. They have just switched off Nigeria. There is no appeal. There is no review.
I'm sure there is at least one person in Nigeria that goes against the flow here and that is an honest person simply trying to get by but with the odds that bad you really can't fault the conclusion that Nigerian traffic so risky that the risks far outweigh the benefits.
Merchants typically run a very fine line between operating their business and having their accounts yanked due to 'excessive fraud', any measures they can take to protect themselves from this happening will be implemented without any remorse, it's a survival thing.
For the record, yes, we block Nigerian transactions, and several other countries besides.
How can dis even be possible? You mean not even one out of the possible millions in a day is legitimate? Haba!
It's sad, but it's really true.
The possible millions make use of free services they're not possible millions of e-commerce consumers.
You wish. If Nigeria had millions of legit e-commerce consumers the situation would be quite different.
There will never be "millions of legit e-commerce consumers" from Nigeria if the main e-commerce gateways such as PayPal continue to block the entire country.
They've already been excluded before they've started.
Obviously, a "which country to do business in" decision is not done by algorithm. That doesn't mean Paypal isn't using objective metrics to make that decision.