I'm not voting in this challenge, just offering up a, hopefully, helpful critique..
The lighting on the flower and butterfly are really nice ahd help to make the yellow of the flower really pop. I'm in two minds about the colour of the background but have come to the decision that it doesn't detract from the image.
The only thing I can see that might be causing the voters to be a little unkind is that the butterflies head isn't completely in focus. But, it's only a small part of an overall well lit, nicely composed image...I give up with the voters here :o(