为什么在条件内调用此函数不起作用？

Question

即使函数返回，为什么samSays在函数内部也不起作用？

function drivinSchool() {

  var samSays = samSaysf();

  if(samSaysf === "hi there"){
    return "talks while driving"
  }
  else{
    return "doesn't talk only drives"
  }
}

function samSaysf() {
  return "hi there"
}

console.log(drivinSchool());