I see this requirement in the Germany Residency Permit instructions, however the general situation seems common among multiple European countries:
How to Apply for German Residence Permit?
The steps to applying for a German Residence Permit are as follows:
Register your German address
Whether you are applying from Germany within the first 90 days or from your home country, the first thing you must do is register your new German address with the authorities. Germany has this requirement and you must fulfill it in order to be eligible for a residence permit.
If you don’t register your address, you could get fined and your permit might be denied. After you complete this requirement, you will get a certificate which you can attach to your documents.
How is one to get an address prior to having a residency permit?
Is one expected to enter into a lease which they then abandon if the residency is denied?