You seem to be referring to a guard clause though in an incorrect usage. return is used to stop the function from continuing which a guard clause uses, it is mainly for readability.
I say incorrect since using return at the end of function isn’t really a guard clause because its at the end of the function which using return has no difference versus no return there.
It prevents nested code mainly
if condition then
-- example
if condition2 then
-- stuff
if condition3 or condition4 then
-- stuff
end
else
-- stuff
end
else
-- stuff
end
Becoming this instead:
if condition then
-- do stuff
return
end
if not condition then
-- do stuff
return
end
if condition2 and (condition3 or condition4) then
-- do stuff
return
end
if not condition2 then
-- do stuff
end
There’s zero difference in the result, they will do the same thing. The difference is visually reading that code.