Growth is very important in the existence of living things. As a matter of fact, every living thing grows. It is a sign of life.
In Genesis, God instructed every living thing He made to grow and produce of its kind. Therefore, it is not just a pleasurable thing to grow, it is divine commandment.
Likewise, every believer must grow in the faith as they relate with God and His Church.
Failure to grow therefore, is unfortunate.