The 45 seconds to apoapsis is not mandatory but it is easy to remember and has the added benefit of usually getting your rocket into orbit. Your rockets, pistolhamster, have already reached the necessary velocity to reach a 82 km altitude. This doesn't necessarily mean your launch was inefficient, it just means your first stage had a higher TWR as your first stage was burning out. A constant burn to orbit requires a lot of fine tuning to achieve, it feels nice when you do it but it is a luxury when attempt to go to orbit.
