Is there an indigenous church? Is the indigenous church able (sufficient size / resources) to evangelize the group without outside assistance?
Does the indigenous church think itself able, vs. do I think it is able, and how do I judge which of us is right, and am I judging rightly?
Given that the indigenous church could evangelize the group, is it doing what it should do?
Am I defining "what it should do" on the basis of my culture and outsider perspective? Who gets to define "what it should do"?
If the indigenous church is doing what it should do, but it is not yet reaching all the segments within a country, is there a role for an outsider?
What is the outsider/insider dynamic?
When does the role of the outsider "end"? What does it mean to "end"? What does it mean to "leave"?
What if the indigenous church is not doing things "fast enough"? Who gets to define "fast enough"?
And for really thorny issues... if a group is spreading fast, how do we know it is spreading "well"? Who gets to judge theology?
And for really, really thorny issues: what happens when an indigenous church starts eyeing Western countries and asking the same questions back?
There are more questions than these, obviously. The main point here is: do we question our own questions?