>>because check this:

void return_number(var number){
STRING* tt="number";
str_for_num(tt,number);
while(1){error(tt); wait(1);}
}


now on main...

return_number(10);
return_number(20);

This should make the engine , error output 10, and then 20, and then 10 and then 20, endless.. but thats not what happens, you get, 10, then 20, then 20 forever, 10 will disapear wuhuhu..