James 4:13-14 Come now, you who say, "Today or tomorrow we will go to such and such a city, spend a year there, buy and sell, and make a profit"; whereas you do not know what will happen tomorrow.
About three years ago, our church decided to open a children's outreach, for local kids only, to be held on Saturday, and I felt led to help. The plan was a success, even though it didn't work. Last Sunday we brought 32 Mexican children to church in the church's 18-passenger van. And our pastor, who took the church from 12 to over 100 in five years, came to Mexico as an evangelist, not a pastor.
In the book of Acts we read that various missionaries, including the Apostle Paul, didn't go where they planned to, but they were still successful. Careful, long-term planning sounds good, and it is often necessary in order for a missinary to raise support. But it isn't always the way God works.