Sitting in wet soil too long makes succulents take up too much water. That leads to root rot, and eventually a dead plant.
For over 10 years I've used a gritty soil mix. It holds enough water for the roots, but never stays wet or soggy.
One part pine bark fines, one part Turface, and one part crushed granite. That's the mix I've used for years.
Short on time? Grab a bag of cactus mix at the store, then mix in some pumice or crushed granite to help it drain.