A blob can occur when a printer does not have AI software to detect failures mid-print. For whatever reason, may it be distance from the print bed, adhesion between layers, temperature, humidity, the universe itself personally undermining my creative endevours as I’m sure you’ve experienced as well. The plastic builds up around the hotend creating a beatiful monstrosity that is usually not as bad for the printer as it first seems. To fix this issue, you can heat up the hotend and gently wiggle out the melted plastic and clean it with a cotton swab.