HomeLAN has interviewed the official CS bot maker, Michael Booth, about the bots he made for Counter-Strike. Here is a small amount of the interview:

HomeLAN - What were the main goals in creating a bot that can realistically play Counter-Strike offline?

Michael Booth - The primary goal was to allow people to enjoy the Counter-Strike experience by themselves, without requiring other players or a network connection. This allows players who are new to Counter-Strike, or who don't enjoy the ultra-competitive nature of the online community, the ability to play this addictive game on their own terms [...].