How are the importance of sutras determined?

I assume that there variations of sects within buddhism that deem certain sutras as more "correct" or being closer to the buddha's teaching. I personally see the Lotus sutra as the "true teaching", but I know that some other sects often see the Flower-garland sutra as being closer to the "true teaching". Is there a system for determining such assertations, or is it more based on text evidence? I have little knowledge with buddhism outside of the sect I'm apart of, so I'm interested in how other parts of Buddhism work.