Can customer feedback be made part of performance appraisal ?

Undoubtly yes, In customer service you directely contact with customer your idea, way of presentation ,your negotiation skill are on live infront of customer so its very clear that if customer satisfaction is up then you are a winner and your performance is unbeaten.

In my humble opinion it would be utterly remiss not to seriously consider customer feedback within performance appraisels.  

At an organisational level, customer feedback can bring huge benefits when collected, evaluated and acted upon properly.

For employees it would be unwise to ignore individual customer feedback.  Often, a customer is able to highlight performance issues that we may not have identified ourselves.  

Understanding what concerns the customers and working to address those issues can bring personal and professional benefits.

After all, an apparaisel should be about improving ones performance not about punishment.

On the other hand, positive customer feedback should surely be acknowledged within a performance appraisel as part of the value you bring to the organisation.

Customer feedback is one of the most important part of performance appraisal. Any corporation with no clients will go bankrupt. If clients are happy and satisfied this means that employees are doing their work correctly whether in speed in  dealing with customer requests and needs, or in follow up, honesty, professionalism. Clients are like babies they need everything right now and in the best quality. They do not know anything about the product sold do not know the employees or the company. They expect professionalism, respect and support. Without any of those three things phone calls and emails will drop on the company about the bad service provided or delay in time. This in turn reflect the work environment and the kind of employees dealing with customers.

YES. I do agre with you100%.