Commitment is one of the four components of Personal Discipleship, including Modeling, Individual Attention and God’s Word.
Commitment has to do with the heart attitude of the discipler (spiritual parent) in regards to the spiritual welfare and development of the disciple. This is a commitment that goes beyond just presenting God's word. The biblical idea of a disciple is more of an “apprentice” than just a student.
Discipling somebody is going to impact your plans. In the natural realm a child takes all of the parents energy. The parent is always thinking about where the child is what the child needs.
Spiritually there is an impact too. Discipling somebody can be emotionally and physically draining. But it is also exhilarating and thrilling and it's so gratifyingly to watch somebody grow but there's also an expenditure of resources and a deep concern (for the disciple).