The longevity (slickness and/or protection) is relative to the product you use. Waxing (using a product to make the car's paint glossy) is not the same anymore. The old term 'waxing' is indeed an old term since years ago car enthusiasts can only buy 'wax'.
Sealants are modern 'waxes' and some are no longer just petroleum based. Acrylic sealants like Klasse or Four Star UPP are water based products and stay on the finish several times longer than ordinary waxes that are carnauba based. Carnauba usually lasts 3 to 8 weeks on a daily driven car. Road salt in winter can strip the carnauba wax from the finish.
I apply Klasse sealant twice a year and carnauba wax (s100) every 4-6 weeks. I also use Eagle One Wax As U Dry spray in between washes to keep the gloss up.
It's usually my OCD that acts up when it comes to my car's finish.
2003 E39 354 Titansilber Metallic 530i
N6SW Schwarz Montana Leder
M Executive Package
BMW AG Sport Package