Most API documentation are a mess.
An API documentation supposed to be clear and easy to understand, there should be no headache to integrate.

Many developers are poor in creating API documentations to integrate to their systems. Maybe because of the amount of work they have at hand and no time to really focus or too lazy or wicked to come up with an easy to understand API integration documentation.

That's were a "Technical Documenter or Writer " comes in. His/her role will be to document complex systems of a developer, in an easy to follow format. In such a way that an intermediate developer can understand. That's just his job, he tests the endpoints, ensures they work & give the right response, then documents how it's done.

An API documentation should have a sample working code in about 3 or 4 different programming language.

Some Industries in Nigeria with API Integration headaches

1. Telecoms VAS(The poorest when it comes to this, in short the have the most disorganized set of documentation. Alot of things here are just word in the winds)
2. Payment processor companies

No company names mentioned, you guys know yourselves and should change.