It always fascinates me when someone makes perfect flower pictures. I can’t point you to someone specific, but look around on Flickr, Smugmug, 500px or any of the other photo sharing sites used by enthusiasts and professionals. You’ll quickly find people who take a lot of flower images, sometimes almost exclusively flowers, and among them are photographers who continuously leave you breathless.
You immediately see when someone’s interest is focused on a particular subject. The images have a certain quality that you even may be able to achieve with the odd grab shot, but that you certainly can’t achieve regularly or at will and consistently at any time.
Like everything else, photography is something that can be learned through repetition and hard work. This may not be sufficient to reach mastery in a particular subject, but without work and repetitive attempts at particular subjects, mastery can’t be achieved.
The rest is passion and imagination.