It's not a good thing if you haven't enjoyed the lesson on differing levels, from you think you have wasted your money to you have not taken that next step forwards.
Different people have different personalities, that is human life, but instructors in all walks of the training life fall into different categories. When you were at school was there a really boring teacher, and another that made the subject fun and "light up". Which one had taught you more?
To go back to flying, instructors fall into different groups. There are those that are just taking the money and building the hours up until Ryanair tell them to come and sit in the right hand seat of a 737. They are generally a product of one of the "sausage factories" and have not spent anytime as a normal ppl, you know, club life and the £100 bacon butty. As they have not enjoyed the club ppl route they have no idea how to nurture someone, all they have to go off is the way they were taught, which is as fast and blunt as possible. There are those at the other end of the spectrum that have been instructing for so long that they have become fed up of it. Let's be fair, if you had 10,000 hours over the last 30 years, and 9,000 of them was either trial lessons or circuit bashing you'd be bored too. Finally there are those that have had a ppl for a few years and then decided to go further and start to teach. These are the good guys, they remember what it was like when they learnt and are generally a lot more supportive and in my opinion make good instructors.
The fundamental point that you raise is one of confrontation. As a nation we don't like it. People like Simon Cowell are held in esteem (of sorts) because he doesn't mind it and will lambast someone if they deserve it. Alan Sugar is the same, as is Philip Green. You get the picture here, these people are rich for a reason, if someone tries to rip them off they don't have it and get stuck in. I am the same, only not as rich sadly, but for certain if I had just paid over £100 and got no benefit as the guy was out of order he would have found out about it quickly. I once actually ordered a CFI to land as I was getting fed up of his hair splitting in the circuit. Nice enough bloke but the way he went on I was paying for him to practice crosswind landings, that I had already done!! So when I said let's land and he said no I want to show you this as you are ballsing it up all the time (I wasn't) and we went for the 4th circuit with him flying and me enjoying an expensive pleasure flight I told him to land as after the next landing I wasn't paying anymore. I told him in the air and we landed, and then he got both barrels
With some folk that is the only way. If you don't like doing that, have a quiet word with the CFI though, you might not be the only one!!