Once upon a time, in a data center not far away, a lone system administrator took the front bezels off several identical machines. Upon completing the work, this individual discovered that the labels for those machines were on the bezels themselves, making it difficult to tell which machines the bezels belonged to.
Shortly thereafter, this lone system administrator configured the front display of those particular Dell servers to display the machine name, thereby solving this problem for himself and retaining the use of the bezels, because they’re pretty.
Once upon a longer time ago, in a data center slightly farther away, a lone system administrator added a network interface card to one of his hosts. In doing this he removed the last remaining card slot blank, which happened to have had a label placed on it. Thinking that it would be nice to retain the label, he attempted to peel it off to place on the rear of the chassis. It ripped into several pieces and was henceforth unusable.
To this day the rear of that host is unlabeled due to initial thoughtlessness followed by continued apathy, which might actually indicate the label was unnecessary to start with.
Moral: If it is your intention to label an object, think twice before affixing the label to parts that are meant to be detached from that object.