Should i really abstract everything

Question

So I need to create a customer system and there aren't multiple types of customers.

Should I still create an interface or abstract class to inherit from?

Answer 1

No. You should only abstract what is needed to be abstracted. You can always come back later and refactor your code if there are new types of customer to be added.

Always keep your design as simple as needed to get the job done.

Don't add abstractions because they look good, you might never need them. Add abstractions because you need them.