Looks like over watering. That can happen when the soil doesn't drain fast enough so it retains too much water causing root rot. These plants are semi-epiphytes that usually grow up tree trunks. The roots run down the tree trunks and on the ground run through the leaf litter on the surface. In a humid environment the roots are constantly exposed to air and get moisture from the humidity. During heavy rain the water on them is highly oxygenated but drains almost instantly. When kept in soil care needs to be taken that water drains away from the roots fast and that there is air movement amongst them, ie. a very light, aerated soil.

Monsteras are semi-epiphytic in that they start off on the ground and then climb up trees. The roots run along the tree trunks exposed to a lot of air and breezes. On the ground most of the roots run through the leaf litter which is usually light and airy. Rain and air humidity is high but water run off is virtually instantaneous. You're better off using a very light epiphytic medium that drains fast and water more frequently.

What you have there is just a leaf with petiole. What you need is a section of stem which the petiole was attached to. The petiole and leaf come from a node along the main stem of the plant. That is also where roots come from. A leaf and petiole on their own will wither away.

<?xml version="1.0" encoding="UTF-8"?><md>Hello! Lol thank you, I get a little stressed out with plant cuttings... So I did end up potting it up. Due to traveling constraints, it stayed in the water cup for about 24 hours before I had access to gardening stuff. One leaf turned a little bit yellow, not too much though. It basically just lightened in color. That was yesterday. Today the leave stems are a little more droopy... I let the soil dry out almost completely, thinking that it was just soaked in water 3 days ago and I know the previous owner didn’t water the plant very often. Is this a bad sign? I did think of cutting below the node where the aerial root is, but didn’t want to stress the plant out more. Is that a better idea than trying to get this whole thing growing? I’m so bad with propagation