Stamps could be completely missing, significantly off-centered, partially missing, or indented into the card, and some cards received two stamps
Sure, you can pay for faster turnarounds, however this then eats into your profit margins
Professional grading guarantees authenticity and condition, with the latter being especially important since its extremely hard to find top Sun and Moon cards in perfect condition
Unless a specific ability, attack or card mentions devolving a Pokemon, its not something you can choose to do
It used to be the case that some Rare cards didnt have a holo foil treatment but thats no longer true
This example is especially sought after, as early Pokmon cards from Japan are renowned for their quality and authenticity.