I pre-emt this by first saying that I have had some of what I believe to be the best instructors, but when I was working in the Kimberley or FNQ, the following was widely agreed:
Not all instructors are w@#kers, but all w@#ankers that you meet in flying are or have generally been instructors
Anyway, agree with most posts here, everyone learns differently, the right instructor for you is one who you respect enough to put the work in for, trust enough to ask the silly (lifesaving!) questions, and who allows you to progress at the best of your potential in the shortest possible time (money!).
Otherwise, vote with your wallet and piss 'em off!
Forgetabowdit