Expertise
Their skills would be in birds, conservation, biology etc
Probably with little funds, using volunteers
Likely to be lacking IT / telecoms specialists in the charity to give them advice...
Maybe lacking the general world weary cynicism of an el reg reader who would assume a SIM on a tracker would be nicked.
A perfectly reasonable error of judgement for someone to make , so I think the slagging off of those charity people is a bit uncalled for, most of us are often quite dismal at things outside our areas of expertise, in a way that an expert in that area would think "total muppet".