The Mandalorian Jango Fett was cloned because his genetic material was able to be manipulated by the Kaminoans to create an utterly loyal, fearless, and aggressive soldier. They did not want force-sensitive soldiers because it would take even longer to train them and they might be less tractable.
For further clarification:
ReplyDeleteThe genetic material may have been manipulated to create an utterly loyal, fearless, and aggressive soldier but at the cost of eye/hand coordination making it difficult to shoot a blaster accurately.