In the real world, and outside of head theology, many christians, probably the majority, keep getting sidetracked from the path they know they should be on by various things. They may even come on the internet and argue/debate about things that are not essential to your christian walk. So they never prioduce the crop they could have produced if they had firmly stayed on the path they should have been on, and not moved from it. They never mature in the faith as they could have, for you mature by evermore practicing right from wrong:
The seed that fell among thorns stands for those who hear, but as they go on their way they are choked by life’s worries, riches and pleasures, and they do not mature. Luke8:14