In addition to the points of sibling comments, their respective starting posititions were drastically different: West Germany got the marshal plan, which benefitted their economy, the East had to pay reparations to the USSR, which meant whole factories, trains, even railroad tracks, all in all amounting to about a third of industrial capacity, were transferred to the USSR.
An East German state (Saxony) also consistently has the best education system among German states.
https://de.statista.com/statistik/daten/studie/201453/umfrag...
In general, East Germany (economically) mostly only does poorly when compared to West Germany, but not to the rest of Europe ;)
[1] https://www.sciencedirect.com/science/article/abs/pii/S01475...
The most popular way to own a company is also inheritance, instead of studying an engineering subject.
This comment was also an answer in the context of the peaceful revolution, where a lot of companies where bought by larger companies from the west, both to destroy their better competitor and get funds from the EU. Such actions are seldomly done by engineers.