I frequently re-install ESXi on my physical host for various types of testing as I normally work with a number of future releases. Although the process just takes a couple of minutes, having to enter the exact same information each time and also requiring a keyboard and monitor is not really ideal. For the majority, this is really not a problem and manually going through the install workflow is fine for most folks, especially as this is an infrequent operation.
However, with some recent customer conversations, I thought it was worth while to re-visit this topic and demonstrating just how easy it is to automate the installation of ESXi with just a single bootable USB device and embedding an ESXi Kickstart Script. Even for infrequent installation and/or upgrades of ESXi for home labs, this can be a time saver, especially if you do not have monitor and keyboard just lying around. Below are instructions including a reference Kickstart example that folks can use as a starting point. For more advanced automation, please take a look at my ESXI Kickstart Resources as well as the official VMware documentation for ESXi Scripted Installations.