Are some countries being very underestimated by major countries?

As a brazilian, we have been following Cape Verde team quite a lot since it's kinda of our little brother of the former-portuguese-colonies family. They tied yesterday with Uruguay but the most surprising is still probably the tie with Spain, that I'm sure everyone is already aware about. Now, I have been wondering in the last couple of days if some teams, usually african ones, are being underestimated by the strongest ones to the point of not doing the bare minimum of preparation and study on t...