bytecode - Lua - slow bytcode -

i have 3 files x.lua, y.lua , main.lua. these files doing mathematics operations (increment , decrement number). when run command

lua main.lua

is faster than

luac -o main.luac -s x.lua y.lua main.lua

please can me why bytecode slower?

i'm guessing main.lua dofile("x.lua") or require"x" , same y.lua.

in case, second form runs x.lua , y.lua twice.