Additionally to analyzing quality of samples, you can also use coverage to predict copy number of extrachromosomal elements. If chromosomal templates and extrachromosomal templates are in a 1:1 relationship, you expect equal distribution of coverage.
Ever wondered how to assess the quality of your NGS data? But get confused about all the fancy tools? Well how about i told you you can assess a lot of problems before even looking at the mapping yet, just by extracting some basic coverage data from BAM files, and extracting the number of reads per sample.