Displaced thresholds are there for a reason, not as a challenge to see who can land before it, on it or 2 feet after it.
As Rusty says, it's usually an obstacle, such
as a public road or fixed object.
The major problem with not complying with the requirements of something like this is, (aside from doing yourself, someone else or the aircraft damage), that you'll screw things up for everyone else.
Those of you who have the pleasure of trying to appease one of the many NIMBY local authorities in this country will know that they only need one piece of evidence that an airfield is not complying with every rule in the book to restrict or even stop flying taking place.
If you see a displaced threshold, comply with it first and ask questions later.
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It wasn't me.