What is the difference between OTC foot inserts and custom made orthotics?

Custom made orthotics, as the name suggests, are made by the podiatrist for the individual's foot type based on the foot condition that may exist. They can be made to be suitable for each person based on their activities and shoe styles. They give arch support and distribute wight evenly,  So they can prevent tendonitis, osteoarthritis, all of deformity , pain and tired feet, while OTC foot inserts are not customized to the individual's feet, as they are mass produced and don't provide the same fit that custom orthotics do. Although OTC foot inserts are cheaper, their much lower quality of fit, and also much less durability (maximum few months vs few years for custom orthotics) makes them a much more inferior option compared to custom made orthotics.