1. Very expensive. Unless you're made of money, you will probably only be able to afford one or two decks in your rotation, or at least the cost-benefit ratio feels like that's all you should do. Especially in Modern, where a typical deck costs you about a thousand dollars. And that's without reserve list cards like Vintage/Legacy.
2. Booster packs feel designed for Limited formats. If you want to play Constructed, you shouldn't even buy the official product straight up. Instead you should buy singles through the secondary market.
3. There's so many rares and mythics and they're all so powerful that pretty much all of the "value" in a booster pack is in a single card. Everything else is seen as bulk from a value perspective. This feeds into points 1 and 2 that makes the game very expensive. I just double checked my Dinosaur deck and the only common I intentionally want to keep in the deck is Commune with Dinosaurs. All the commons just pile up everywhere and take up space. You have a site like Card Kingdom that has to get creative and sell stuff like the Rookie Decks and Battle Decks to offload all of their bulk. It's like the only reason commons exist is to be played in Limited, and those cards take up more than half a pack.
