In my opinion, the panels were fine, they just did not control the installation process. Among other things saved on fasteners: the panels have 5 holes for dowels in the center and 2 on the edges on each side, the middle was not fixed, so they bent.
And the sun and rain and moisture and temperature fluctuations and wind walking between the battens did their job.
I'm also inclined that this is because of the economy of installation.
Well, even with a glimpse, judging by the photo, it is clear that the seams are not foamed, polyurethane bent and crooked, the only good thing is that the clinker holds firmly and still does not fall on someone's head.
The heat could have made it go that way.
Polyurethane shrinks, there is no rigid base.