GO:0090737:   telomere maintenance via telomere trimming
A process that contributes to the maintenance of proper telomeric length and structure via the activation of telomere shortening pathways that compensate telomerase-dependent excessive telomere elongation. Telomere attrition is mediated by a mechanism which involves the generation of single-stranded C-rich telomeric DNA, and the formation and removal of double-stranded telomeric circular DNA (T-circles). Telomere trimming is an independent pathway to recombination-mediated telomere elongation and the well-documented gradual telomere attrition that accompanies cellular replication.