Why do you not inform about names of the CEO's, directors, ministers etc.?

Because of the value of the complete content. Names of individuals usually change much quicker than the general contact details.
To be up-to-date with the names of the staff, a regular individual mailing would be necessary, and please understand it is a real worldwide directory which requires a permanent cross-cultural communication. This would enlarge the costs and all efforts enormously. If the future allow this supplements, we would be glad to provide you with this data, too.