Because the first person who explicitly predicting that theory is Peter Higgs.
There are a group of scientists who worked together to developed the Higgs Boson ttheory such as Jon Botterworth , but the particle finally named after Peter Higgs out of respect since he's the one who 1st explicitly predict it
In July of 2012, physicists found it. This last boson was named the Higgs, after the British physicist Peter Higgs, who was among the first to propose its existence.
