This isn't a definitive answer, but the album's lyrical content suggests existential themes of reaching out for some kind of genuine human connection within contexts that are dehumanized, depersonalized and faked. The image resonates with these same themes by presenting a glossy image of success --a deal between two wealthy power-brokers, backstage at a movie studio --and subverting it with the fact that one person is literally on fire, but both are pretending not to notice.
The concept behind "Welcome to the Machine" and "Have a Cigar" suggested the use of a handshake (an often empty gesture)
The album's cover images were photographed by Aubrey 'Po' Powell, Storm's partner at the Pink Floyd design studio Hipgnosis and was inspired by the idea that people tend to conceal their true feelings, for fear of "getting burned", and thus two businessmen were pictured shaking hands, one man on fire. "Getting burned" was also a common phrase in the music industry, used often by artists denied royalty payments. Two stuntmen were used (Ronnie Rondell and Danny Rogers), one dressed in a fire-retardant suit covered by a business suit. His head was protected by a hood, underneath a wig. The photograph was taken at the Warner Bros. studios in Los Angeles. Initially the wind was blowing in the wrong direction, and the flames were forced into Rondell's face, burning his moustache. The two stuntmen changed positions, and the image was later reversed.
Straight from Powell, Storm, Roger, and David. The industry burned them and other artists. They had no intention of being commercial they only wanted to make music. Listen to the lyrics of Have a Cigar and pay attention. Hence Welcome to the Machine. The industry was just a machine cranking out top selling albums. Once you quit or fell short bye bye.
Think the guy on fire is supposed to be Syd Barrett who is credited for starting the band and Roger Waters is standing in his shadow, almost like all of Water’s creative, introspective, wise rhymes he made came from something that caused him great pain. Syd is trying to carry on “normally” in the businessy “real” world while his schizophrenia is burning him alive. I think the whole album is about Syd, wishing he was here -mentally and physically- with the band. I read the schizophrenia (that Syd believed he had, though never clinically diagnosed) modified the way he walked, always on his toes. Syd has his back turned to the sun while Roger is looking right at it with Syd in the way.
here is a philosophical answer by my own perspective.in this picture two men are looking same and make a deal(try to make a good relationship to eachother) with himself but one man is on fire it signifies that fire-man was in guilt and cant see directly looking at himself(suited booted gentleman).he is burned in this sense.