This was the birth of what we now call "Freeze Time". It was added to prevent players from rushing immediately and to give them time to buy equipment without losing precious seconds of the round.
But the first time you hear the "Follow me" radio command and rush up the ramp on de_dust with a pump shotgun in 640x480 resolution... you’ll understand why we fell in love with this game. Download Counter Strike 1.2
While later versions focused heavily on "Defuse" maps (like Dust2), version 1.2 was a major turning point for the Hostage Rescue This was the birth of what we now call "Freeze Time"