How do you know when your sd card is messed up?

You may suspect your SD card is malfunctioning if you experience frequent data corruption, such as files becoming inaccessible or unreadable. Other signs include slow transfer speeds, error messages when trying to access the card, or the card not being recognized by devices. Additionally, if you notice unusual noises coming from the card or if it becomes physically damaged, these can also indicate issues. Regularly backing up your data and running diagnostic tests can help identify problems early.