As a cross-cultural church planter, Paul sailed around the Mediterranean, planting churches in multiple cities. The longest he remained in any one city likely was his two-year stint in Ephesus. Other missionaries remain in a country for decades, seeing little fruit while paying the price of laying a foundation that future workers will build upon. God puts missionaries in places for various amounts of time. But regardless of how long God will place you in a field of service, while it may be tempting to stay among people you come to love, your goal should be working yourself out of a job. Several ways of approaching the job will help this happen.
Have a clear goal. With no plan for what God-given success on the field will look like, you can stay indefinitely on the field.
View yourself as a coach and facilitator behind the scenes. Some missionaries relish the idea of leading a new church or preaching regularly. Instead, purpose to never be at the front of the ministry. Quietly disciple and prepare nationals to lead the ministry.
Conduct your ministry in as reproducible way as possible. If you introduce expensive or complicated ministries and ministry methods, you will inevitably create a dependency on yourself and slow the growth of the ministry and its transfer to indigenous leaders.
Have a high view of the Holy Spirit in those you leave behind. It may be tempting to stay until circumstances are perfect. Paul was able to leave after shorter stays because he had great confidence in the Holy Spirit who resided in those Paul led to Christ as they sought to lead the church and solve problems. “I myself am satisfied about you, my brothers, that you yourselves are full of goodness, filled with all knowledge and able to instruct one another.” (Rom. 15.14, ESV)