People downvoted me but this was kind of my point. USB drives do usually work, but I still have experiences however rare, that a particular server and USB combi

People downvoted me but this was kind of my point. USB drives do usually work, but I still have experiences however rare, that a particular server and USB combination is not working so when there are situations that I have to travel somewhere and be 100% certain that an OS install is going to be possible I still feel the need to have an optical drive.