The Gross Domestic Product (GDP) is simply the monetary value of goods and services produced in a country over a period of time. Therefore, it is the most reliable metric used to measure the economic health of a country.
Some of the ways to grow a country's GDP are increasing population may be through migration or more birth other ways can be training skilled workers I'm giving them access to resources to create high-value goods and services.
Over the years the European Union has experienced mass migration of its citizens and some of those are highly trained citizens who are looking for tech rolls.
Another issue with the European Union economy is energy which is very important for any economy to grow and fuel the economy. The European Union does not have any large energy reserve the only place with a large fossil fuel deposit is Norway and the United Kingdom which are not members of the European Union.
The Netherlands which are major players in Gas production has declined back a lot in production. But all this doesn't really matter because the European Union gets really cheap gas and energy from Russia but after the Ukraine invasion that has been a problem. However, the European Union has invested a lot in renewable energy which might not have any significant effect now but in the future.
The energy problem has affected production a lot recently Volkswagen plans to shut down some of its plants before changing plans. And also the biggest BMW factory in the world is in the USA which explains a lot.
Another obstacle that has hindered the European Union's Economic Growth is their strict regulations