What could be a consequence of failing to properly shuffle a deck?

If a deck is not properly shuffled, it can lead to predictable or insufficiently randomized card order, which may result in players drawing cards in a way that does not reflect a fair distribution of their deck. This situation can trigger concerns about manipulation, whether intentional or not, since players might appear to know which cards are coming up next. Consequently, such a failure can lead to accusations from opponents regarding tampering or unfair practices, which could result in penalties under tournament rules. Maintaining the integrity of the game and ensuring a fair environment is crucial, so proper shuffling is a fundamental requirement in tournament play to prevent any perception of impropriety.