SAPUI5 application &1 was not uploaded or registered successfully

What causes this issue?

The upload of an SAPUI5 application, component, or library into the
SAPUI5 ABAP repository &V1& ended with errors.

System Response

The upload or the registration in the application index was not
successful.

How to fix this error?

Check the errors and warnings in the log output.

Procedure for System Administrators

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

Error message extract from SAP system. Copyright SAP SE.