Here's why:

* Temporary magnets are made from materials that are easily magnetized but lose their magnetism quickly when the magnetizing force is removed.

* Steel is a ferromagnetic material, meaning it can be easily magnetized. However, it also loses its magnetism relatively quickly.

* Permanent magnets, on the other hand, are made from materials like neodymium, which retain their magnetism for a long time.

So, while a steel paperclip can be temporarily magnetized by rubbing it against a permanent magnet, it won't maintain that magnetism for long.