As Meyer and Carl Zeiss Jena were both State run companies it's highly likley that it was deliberate that Ziess made their few higher end lenses. They were supposed in test reports to be slightly better than the Meyer lenses.

It was the sales and marketing of the lenses that thrust the Ziess lenses forward as "Top Draw" I kept a few old 1960's photo magazines from when I was at school and it's clear in all the adds for Praktica and Exacta cameras.

I still have a Meyer Lydith 29/30mm Exacta fit and used a later version, Pentacon 29mm, for a while on a Spotmatic. Personally I've never used a duff or bad Meyer lens, I have 2 Exacta fit Domiplans which I've never used at all.

On the other hand in 1971 I bought a S/H Prakticamat with a Ziess f1.8 Pancolor lens, it was sharp but exposure wise the camera was not consistent and I wasn't happy with it. One day I discovered that the lens didn't always shut to the correct aperture every time.