Supply Convoy

The real expense of starting a colony, especially on a world that needs some terraforming, is not scouting or even the initial settlement, it's supplying the colony until it can become viable. Until a colony is ready to support itself, food, consumable goods, resources and sometimes even water needs to be shipped in on a regular basis for the colonists to not just survive, but to thrive. This makes colonization very expensive on marginal worlds like Derrickson's Landing, and explains why the colony leaders were so willing to accept military backing, which meant a large portion of free supplies would be shipped in.