If one customer made a personal complaint because of their own opinion, but the action needed to be taken will affect other customers, what do you do?

The best option is to explain things to the customer.  The customer is just saying his personal complaint but he is not demanding for an action however make sure that and assurance that his comment will be forwarded to the management will give a positive response to the customer.

Hello to all. Action will be based upon the complaint or the bad experience which customer went through. This is the reason why nowadays all the major companies and the organization has standardize policy towards customer service. If issue is under the policy then resolution can be given easily but if issue is beyond the process then without going an argument with customer, a customer service agent should provide a feedback form and ask him/her to fill up & the same to be shared with concerned team immediately.

Now two vital things, the service agent has to be very polite and has to have good listening skills while dealing with the customer. The entire conversation or the scenario has to be dealt with patiently and should not create any chance of an argument, remember we have to gain the trust.

This is why a sales agent/ customer service agent takes a significant role for a company or organization.

After listening to the customer's complaint carefully, let the customer be comfortable and explain things to him/her in detail. If you find a rational and on point complaint from the customer, contact the concerned department, take remarks and feedback from the customer in handwritten form and forward it to the superior management. And if the customer has pointed something out (may be a flaw or a breach) by his/her personal opinion, note it down and take the information to concerned authority to take care of the issue.