(Their goal for Samaritan is for the A.I. to take control of the world and run it without pesky parameters like humanity or empathy, and only acting on data alone.)

Person of Interest revealed that The Machine was created in response to 9/11 and the need for an A.I. capable of searching through vast quantities of data to seek out potential threats. What made The Machine unique is that it's creator Finch gave it empathy, so it doesn't just act on cold hard data and can understand things from a human perspective. Of course, The Machine wasn't the only A.I. created with these parameters, with Person Of Interest season 3 revealing the existence of a rival program dubbed Samaritan.

Samaritan was created by Arthur Claypool but while the government shut the project down, its drives were later recovered by Decima Technologies. Their goal for Samaritan is for the A.I. to take control of the world and run it without pesky parameters like humanity or empathy, and only acting on data alone. Once the A.I. is up and running its starts recruiting agents to its cause and identifying and eliminating threats to itself and its goals. Its capabilities are beyond that of The Machine too, being to target and analyze individuals down to the most minute details.

https://screenrant.com/person-interest-show-samaritan-ai-explained/