Battery life depends on multiple factors. These include efficiency of the individual hardware components, how the software manages power, battery capacity and individual usage pattern. The last one is arguably one of the more important ones especially since no 2 people use their phones in exactly the same way. Take that into consideration the next time someone posts their battery life on a thread.
Another thing to note. Try not to base battery life entirely on SOT numbers. SOT is directly correlated to usage pattern. In order to get a better picture, compare SOT numbers to the overall uptime of the device. 4 hours of SOT might not sound that impressive but 4 hours of SOT with around 16-17 hours of total uptime is actually not bad.
Battery life will be different for every user even with the same device because we all use our phones differently. As such, the next time we post anything about our battery life, don't forget to not only post SOT times, but also device uptime, battery chart and usage stats and give an overall rough summary of your usage pattern.