I saw this opinion(or fact?) "chkdsk /r command examine all the files and then start the fixes." from the MS support engineer.

I understood this answer was about chkdsk /r in stage 4's working method. the chkdsk running on prompt trying to read, scan all clusters in the user file and when it scan is finished, detected bad cluster is replaced or if could not replace, just pass and so on to next file.

Am i understand about this method correctly? so support engineer's answer is clearly correct? i just wanna verify engineer's answer. so need correction from expert who clearly know about this correctly.