title: Why do some projects that use typescript/webpack also use babel to finish compilation
body: <p>I've noticed some web projects using typescript and webpack also use babel to finish off the compilation. For example, they use ts to compile to ES2015 and then use babel to compile to es5. Why not just use ts directly to compile to es5?</p>
  
  <p>Is it in the case the project also has js that needs to be compiled so they just use babel for everything? Or what am I missing?</p>
  
  <p>Thanks.</p>