In QC If we Add Scripts to Testlab then the default Status of the script is in No Run ,then if we close script in middle of the execution then the status will be Incompleted then if we pass all the steps then that testcase will be in Passed Status .When we fail any step(s) in a testscript then that testcase will be failed Status .We can also Customize the Status Field values by adding more or less values everything willbe based on Company .Some Company has Status Like 'deferred' or 'N/A.