When examining this sonnet within class, a lot of people said they would be insulted if they were the subject Shakespeare had written this sonnet for. However, I believe that there is a genuine meaning behind this sonnet. If an individual prizes their worth all on their appearance, it's a truly insecure person that would find this poem to be degrading. Perhaps Shakespeare's comparisons can seem harsh to some readers, but I find that this sonnet has underlying meaning.
Essentially, Shakespeare is saying that in the terms of beauty defined by the society at the time, the subject of the poem would not be considered "beautiful" by the judgmental people. However, I believe that what Shakespeare is trying to highlight is that the subject is beautiful in their own way. Is everything based on appearance? If the subject is the dark lady, is her music not beautiful? Just because her skin is not so fair and her hair isn't the ideal color, does that make her unsuitable? Due to the critical lens of society, anyone who would find this particular subject to be appealing would be in a rare form. But Shakespeare is a man who can be assumed to examine subjects thoroughly, learning about their true personalities and ways of living. Perchance it is for the reasons that cannot be visible to the naked eye that Shakespeare indefinitely feels love for the subject.