A comprehensive car diagnostics is a rather extensive and all-encompassing process. It involves checking for potential faults or errors in all available systems.
By conducting diagnostics on a regular basis, problems can be detected early, right from the moment they arise. Conversely, if defects are ignored or go unnoticed, this can lead to much larger issues in the future.
Furthermore, at some point, it could even pose a safety threat to you or other passengers on the road.