The following scale is used on grapeobserver.com to record the quality of wine:
Exceptional, Outstanding and Very Good wines are wines that are highly recommended, and have special attributes such as long length, complexity, intensity of fruit, resounding typicity and harmonious balance. Buy them if you can.
Good wines are well made, show typicity and won’t disappoint.
Acceptable or Sound wines are everyday or unremarkable wines that are fault free.
Poor wines are wines that I did not enjoy or like.
Faulty means the wine appears to have an issue. Cork taint, brettanomyces, volatile acidity and premature oxidation are some common causes.
The descriptions of the wines are more important than the scale.