Lick paint on gloss

HiI have had Lick painted applied to Walls and also woodwork (doors and skirtig etc) however on certain areas which have been glossed historically (frames and skirting) the paint is peeling. The paint says it is multi surface, however I do appreciate that these paints won't be as good as designated wood/metal paints.The manufacturers guidelines says that for doors you just need to "light sand" https://www.lick.com/uk/blog/how-to-paint-furniture-wood-metal-and-other-internal but everything else relating to wood seems to suggest sanding and priming (which is what I would expect). Would it be safe to assume, in line with good practice, that anything glossed (door or otherwise) should be sanded and primed and not just sanded? Would welcome any views on what professional standard would be here