Not having/being able to justify the money to do it in-house? A great example of this kind of challenge working well is Boston's MBTA live tracking transit dat

Not having/being able to justify the money to do it in-house? A great example of this kind of challenge working well is Boston's MBTA live tracking transit data and stop prediction data. They released an API and said "hey app devs, go make apps!" and now there are a variety of apps on several platforms. Some solve different problems than others and had they done one in-house app it is very unlikely it would have satisfied all the use cases that the available apps satisfy.