Oddly the one that took AGES
was tracked... and vanished for months.
Also 90% of the time tracking internationally falls over - especially FROM the UK. I well recall the terrific row I had with the post office when one FROM me to Canada vanished completely. They said what did I expect - I should have paid for datapost. I don't think so.... it is so expensive it would have cost A LOT more than the package was worth.
Now, within the UK - even tracked - I have lost quite a lot. My favourite of all time was the signed for one to renew my Canadian passport - containing all my original papers. In the end I became worried, so I phoned the High Commission - who said yes of course they had it, and the new passport was about to be mailed back to me.
Two years later it was still showing on their website as in transit
There was also a package to my daughter at Uni, which I got compensation for and which rolled up 6 months later. I did not return the compensation. She;'d been slipperless (among other things) all that time...