The thing is, for people that buy a lot of packs, or draft a lot on MTG Arena, its fairly easy to obtain all the rares in a given collection but at the same time lack several mythics
Most control decks on the other hand are either going more the direction of the agro decks and getting card advantage alongside their other effects from cards like Consecrated Sphinx or planeswalkers or they are running a card advantage engine such as Life from the Loam
Easy as
WotC internally calls it the Thalia problem, so with this example, you might have two of the Dark Ascension art, one of the Innistrad: Crimson Vow , and if you wanted the Multiverse Legends one, you'd only need to craft one new rare wildcard to allow four of that style to grace your decks
This is great for something as simple as questing with her one or even two times a turn
This will depend on your personal preferences, the number of players, and the formats