THOMAS RHETT has written his share of hit country songs . . . but the most surprising part about that is how shocked he is when he finishes one.  And his co-writers are just as surprised as him.

He tells CMT, “Every time I finish a song, all the songwriters always look at each other and go, ‘Can y’all believe that this is even possible?  Like, how did we come in here, not having one thought or one idea and we left with a song?'”

He does use certain tricks to push him through.  Sometimes he takes a lap around the bus or the studio, other times he’ll pace . . . and a shot or two of coffee also helps.  Basically, whatever it takes to “change up the vibe and the energy.”

He says the entire process is kind of a mystery but extremely rewarding.

Quote, “[I’ll] walk in and be like, ‘I don’t know what we’re gonna say,’ and then you say it, and then it ends up on a record, and then it ends up on the radio, and then you hear people singing it.  It’s like the most full-circle, amazing thing ever.”