How do you know when a bloom is naturally fading vs when something is actually wrong?

[SakuraDrops]

Compare the blooms in this photo: Bloom comparison - Album on Imgur

Is this the natural way blooms fade?
If something is wrong, does it appear on the blooms? If so, what would be some signs that blooms exhibit that the plant isn't doing well? Spots or discoloration?

I want to add that, this orchid has been in bloom for months, and has new buds forming. I just never am sure if I should worry or not when the blooms start to look like this! Also, I do not mist blooms.