I'm new to Android myself having gone from an Iphone 4s to the HTC One and I absolutely love it. Before I made my choice I spent about a week doing research and comparing the phones I was interested in which oddly enough did not include the HTC. I looked at the GS4 and the Moto X initially online and then went to Best Buy to get my hands on them and while I was chatting with the Best Buy mobile folks it was suggested I might look at the One as well. So, back to the drawing board I went and after a bit more reading I eliminated the S4, it sounded like Samsung just loaded that thing down with bloated software, and other features which sounded nice but were either not that nice or stuff I wouldn't necessarily use that often.
So, that left me with the HTC One and the Moto X and after thinking about what I use my phone for (outside of phone calls obviously) I decided on the One because I liked the idea of the front mounted speakers, I liked the build quality, and the 32gb starting model (which is more than enough space for me especially using google to stream music instead of storing it on my phone) and the One felt better in my hand when I compared the two at the store.
So, there you have it, that was why I made my choice and I ended up with the blue HTC One and couldn't be happier.