The lob is like religion–very few people will argue against it on the Internet.
The lob us the most versatile stroke in the game. One can lob for offense, defense, or neutrality.
The lob is typically classified as offensive or defensive. The offensive lob is hit low with topspin–barely clearing the head of the net opponent. The defensive lob is directed high and the goal is to regain and recover court position.
The lob must be practiced often and this stroke will be your best ally on every level of play. I bet your tennis instructor ignored the lob at your lessons.
Take it from the pro and call me to learn the lob stroke.