Nearly 100% of circumcised males never asked to be circumcised (since it was done when they were only a few days old). A number of those men attempt to create new foreskins through a process called foreskin restoration. This is usually done by slow stretching of the shaft skin ('tugging') by manual methods or various devices, analagous to stretching piercings, so that it eventually covers the glans when flaccid.
Restoration typically takes several years, with results eventually appearing uncircumcised. Restorers report a better sense of well-being, and improved comfort and sensitivity.