About 5 years ago I started marking each item I purchased, obviously not those things that only had an expected life span of a few weeks/months, but those things that I expected to last for years. Waterproof Felt-tip pens have been best.
What has surprised me is the longevity of some items and the relatively low number of uses that other items managed to achieve. I'll not name any item but one, that is used only at Christmas, managed to fail after 3 Christmases, that's fewer than 12 uses.
Perhaps I would have been better off, not marking it and, not knowing how fragile it really was
Yes that may be so, but on the topic of pens - I've noticed recently that the ink 'reservoirs' inside the see-thru ink-tubes in most modern rollerball pens have a very low 'cut-off' time or working life. My drawers are full of 'em ... pens that is ... running on empty ;o[