Why don't construction prices go down?

You're really sticking your neck out there...

Well, if you had taken care of it, you would have noticed the mistake when laying the first row of stones. Presumably, there won't just be too much plaster on it. Then the mistake would be easy to fix.

We assumed when we hired a local company with a good reputation that it is not necessary to check the entire construction daily with a tape measure...

If the plan says 4.075, I expect at least 4.07 can be built... I do not accept the excuse that cutting does not look nice for [KS] and aerated concrete - it cannot be any simpler

We assumed that when we hired a local company with a good reputation, one would not have to check the entire construction daily with a measuring tape...

If the plan says 4.075, I assume you can at least build to 4.07... I do not accept the excuse that cutting doesn’t look nice with KS and aerated concrete – it doesn’t get any simpler than that

It’s not necessary to do this daily either. But at least the important measurements after laying the first row. Because even the best mason can simply make a mistake.

You’re about to tell me that construction still works in millimeters.

I am talking about construction, not an architect who draws up the plans. In practice, millimeters don’t matter on the construction site. That’s common practice.

We’re talking about raw dimensions without plaster. And yes, I expect work to be done accurate to 5mm. No matter what kind of practice you know from the construction site.
It is more understandable that the interior dimensions vary slightly with interior plaster—but maybe by about a centimeter, but no more than that. There must not be more.

When I place orders, I stand next to it and measure myself. There is no room for shoddy work.

Wow! You buy a Mercedes and drive to the factory and stand next to it so that there are no defects. You order an iPhone and fly to China and stand next to it.
No! I commission a product and may, no, must expect that the product is delivered as ordered. Unfortunately, it is extremely embarrassing in construction that you sometimes have to watch the craftsmen closely. That must simply not happen. With cars, it is taken for granted that the gaps fit. Why not with a house, which is much simpler to build?

I would say he probably doesn’t care enough. He only comes around with the problems when it’s too late.

Lately you’ve been talking more and more nonsense. “He” wouldn’t have to care, the contractor must deliver properly as ordered. And “he” is not responsible for the problems, but the contractor is.
I also don’t say to you: “If the product ordered from Amazon arrives defective to you, you are an idiot because you didn’t care for proper production. How can such a thing happen? You have to stand next to the producer and ensure the product is correct yourself!” That’s how you talk to the OP. That’s unacceptable.

You don't have to do that every day. But at least the important measurements after setting the first row. Because even the best bricklayer can sometimes make a mistake.

During the shell construction week, we were on site every day with a tape measure and laser measuring device and checked everything, including window and door openings, as well as the distance to the timber frame corners.

Warum nicht beim Haus, was deutlich einfacher zu bauen ist?

Because the house is being built by hand. Humans make mistakes, machines do not. However, there are still mistakes. I also don't understand in this thread why an error of almost 10cm is being attributed to the OP as a loss of control. It was not about what would have happened, but what could happen.