Well said Nirlep.. Me too thinking
I feel, images should speak for themselves, and an image which doesn't need words for describing itself makes the most impact. Some images go beyond the boundaries of physical expression and cannot be described due to limitations of words (or language). Such images are best left to the viewers' discretion and perception, which may differ from the creator's version.
I agree with Ganesh, when he says, some images may require words, but do not agree with Ganesh's take on your image 'The tiger I never saw'. I feel, that image speaks for itself, I had connected the image(thumbnail) with tiger, without even reading the title.
I couldn't connect with the image of the Syrian child with her hands raised, till I read the description. The image didn't really make an impact on me, until I read the words that went with it.