Literally: suitable – material – suitable – place
Alternately: “The right person in the right place.” Placing someone in a position or job that matches their character and skills. Finding the right person to do a given job.
Notes: 材 originally means “lumber,” but by extension can mean “talent.” 人材 (jinzai) is “a capable person” or “human resources,” “personnel.”
Apparently some people write 才 instead of 材, but this is an error.