In my experience the main problem with the lightning port is that it collects fluff and debris. Each time you plug in a cable it compresses the junk into tthe bottom of the port, it then makes it impossible for the plug to seat properly.
Using a tooth pick or something similar and some compressed air it's usually possibly clean the stuff out.
I must have fixed at least half a dozen iPhones belonging to friends using this method.
There are plenty of online videos and instructions how to do this.
