Hello Mark
It would seem that the Bear has a sore head today and isn't his usual tactless tactful self.
The star ratings are an arbitrary method of classification based upon a perceived level of skills.
Skills such as the ability to read and understand drawings, previous experience in model making, practical skills and access to tools / equipment.
1 star is theoretically an easy build but a beginner might struggle either with reading the drawings or having access to the necessary tools.
2 star would supposedly require an average ability (whatever average might be)
3 star are considered by an expert to be more difficult than 2
4 star are very difficult and should only be attempted by someone who has a couple of years to spare.
Basically you pay your money and take your chances
Paul