I was talking with a beginner photographer the other day and I was asking about her recent trip. She said it was good but she took twenty or so photographs and only one was "good enough". She seemed upset or down on herself for only getting one keeper after twenty or so photographs. I told her that was an excellent "shooting percentage". On a typical day for me I might take 200 photographs of a sunset. If I get 2 or 3 out of those 200 that meet my standards I am pretty happy with that! Sometimes I will even go out on a shoot and not even get one photograph that meet my standards. Just wasn't my day. We all have those days! Don't be hard on yourself, it happens, it's part of the craft.
With time and practice your shooting percentage may improve, but the great thing about the digital age is that we don't have to buy film. Shoot away! People don't know that the one photograph I display took me 200 tries to perfect, nor do they really care. All they know is that they like the photograph. I have never had anyone ask me how many tries did it take to get that photo.