quality of genomes in databases
 

hello,

How one can estimate the quality of sequencing and assembly of genomes in databases, for example, NCBI? Are there any objective 'numbers' from which one could understand that a given genome was sequenced 'well', i.e., the level of errors is low and a small fraction of nucleotides is missed? Concerning the latter it seems to me the coverage gives an estimate, but I am not sure and I have no idea about the former. Or may be there are other criteria of quality in NCBI and if so then how to find them?

thanks.