The nagging customer represents a tribe of customers will try to bully you.
They won’t listen to your phone call, they will use the incorrect version of the application manual, they will whine about your app size by comparing with a totally out of context app that their friends have built years ago.
They will blame you for not using the latest API that is still in its beta and as a standard practice, you shouldn’t use it on the production apps.
And not only that, they’ll find your faults when things go wrong because of reasons outside your control.
If you, the project manager, do an outstanding job, you can lower this number to 1%.
But you cannot eliminate them completely.
The thing is, defending what you have done and getting frustrated about why that particular customer does not understand the right thing doesn’t solve the problem.
They are like that only.
And even if, if you find a magic wand and somehow figure out how to fix the customer’s mindset, it doesn’t work as that 1% keep changing.
Is there a way to know who that 1 % of customers are?
If you are in the software development service business, you have to accept that some customers are like that. Not to whine about why they exist but to accept them and do what’s possible.
Given you are not blessed enough to change how the software development service industry, it would be good for your business to make it easy for them to “catch” you, learn from those experience and align your business decisions accordingly.
This is not included in the theory of Project Management but if you do, your business will suffer less. This is applicable more when your organization size is small and you, the project manager is the one who is responsible to “solve” the problem.
It is certainly not comfortable and it is obvious that you won’t like it, however, it is, certainly a wise thing to do.