How hyperthreading is useful in kvm based guest VM?

We are creating virtual os threads inside guest os but the actual physical core is on the host machine. Will hyperthread = true in guest VM config make any difference? I can visualize how hyperthreading works on the host as it has a physical core, but VM has virtualized os threads so it hard for me to visualize hyperthreading inside a VM. Can someone please explain to me how it will be useful.