Quality is the opposite of Taste. Taste is related to Cake. Cake is related to Egg. Egg is related to Cholesterol. 
Plan is related to Perfect. Perfect is a different concept from Bad. Bad is the opposite of Favorable. Favorable is a synonym of Useful. 
Quality <--Antonym--> Taste <--RelatedTo--> Cake <--RelatedTo--> Egg <--RelatedTo--> Cholesterol 
Plan <--RelatedTo--> Perfect <--DistinctFrom--> Bad <--Antonym--> Favorable <--Synonym--> Useful 