Udemy's appeal for NCP-AII prep is choice and price — independent instructors publish practice-test packs and courses covering NCP-AII's server bring-up, control plane, cluster test and verification, and troubleshooting areas, usually at a fraction of official training rates.
The gap is the same one that shows up across any self-paced marketplace: a course or practice-test pack can't tell you specifically which of NCP-AII's server bring-up, control plane, cluster test and verification, and troubleshooting areas you're actually weak in. You finish knowing you worked through everything, not knowing whether you've retained enough to pass.
Edureify's Diagnostic maps your understanding across NCP-AII's server bring-up, control plane, cluster test and verification, and troubleshooting areas on day one, and the Readiness Score keeps updating as you practice — so instead of a vague sense of completion, you get a specific, evolving answer.