Renovate wooden windows and wooden shutters please help

No, but he is urging for payment. What to do?

Request a correction and withhold the payment. It looks as if the apprentice worked on the first day and the master was on vacation...

I have just painted our house several times and it doesn't look that bad anywhere. And I have never done it before. That is definitely not right and his explanation about getting closer is a complete joke. Water can also penetrate the heavily peeled areas, as it seems. So it is not only an optical issue but also an absolute fail in terms of wood protection. I'm really sorry. Definitely do not pay and seek help.

a few more details. The grooves were not sanded or not sanded well enough. The old completely chipped spots are still visible, as are cracks, the paint application is uneven and the metal parts should not be painted. It really looks like a hobby craftsman painted it in the installed condition

Yes, that is also very clearly visible. Really a shame that this was delivered by a company specialized in that.

Even though the work was undoubtedly done poorly, may I still ask how you got in touch with the painter? Is it a local from the area, from the Yellow Pages, or from the internet? Perhaps also how extensive the job was (just brushing over, sanding, glazing / painting). Maybe even the number of shutters and the contract amount? That might possibly help others to better assess such jobs and perhaps avoid making mistakes in awarding contracts?

Where he is actually quite right about the spacing itself. So in window construction, there are very precisely defined tolerances. Nevertheless, this is unacceptable and you can see that even from 2 meters away.