Balancing is normally done with values unsuitable for direct action, but only after the opponents' bidding has demonstrated weakness or minimal strength.
The aim of the tactic is to find a makeable or nearly-makeable contract for one's own side or to "push" opponents a level higher.
It is important to be able to enter the bidding on hands in which one has about 9-11 high card points (HCP).
The difference stems from the fact that on a minor suit you can double and - after partner's response at 1-level - can rebid 1NT with 15-17 HCP.
However, on a takeout double over a major suit, partner will seldom bid at the 1-level.