After a television report about online shop trust seals, I wrote a blunt article: why should I pay for a logo customers might not recognize if its checks were unclear? I described a sales call to my shop Groovy Gadgets in which the seller struggled to explain its value. That was my experience at the time, not proof that every seal is useless.
Ask what is checked
A familiar logo may reassure visitors. Look further: is the shop assessed, how often and what can a customer do in a dispute? Check whether a shop displaying a seal actually belongs to the program. The Dutch Consumers' Association compares current seals and stresses that they offer no complete guarantee, though they can add reassurance.
For a retailer, the decision is wider than cost versus extra sales. Which standards must you meet? Do customers receive better information or a clearer complaints route? Does the seal fit the products you sell?
Revisit my old conclusion
In the first version I drew a broad conclusion against seals from one investigation and one sales call. I would be more careful now. Judge a seal by current checks, recognition and help when problems arise. If it is only a picture, it adds little. If it encourages verifiable behavior and gives customers a remedy, it may have value.