What is going wrong here?

[SimonBridges]

Under or over watering?
Too much or not enough light?

If the browning leaves feel dry then under watering, over watering if they're soggy.
They need very little watering, full sun and generally neglect i think.

Possibly over-watering? Succulents like to sit in gritty soil with good drainage. They need at least 3 to 4 hours of direct sunlight, and don’t like sitting in wet soil. Water sparingly every week or so, taking care not to wet the leaves.

Looks like overwatering to me because that brown stuff looks like mould. Sempervirens need very sharp drainage so it's important to add lots of grit to the soil and they need full sun.

I think it'll be over watering then. I've been watering daily along with the other pots and containers.
They are in the sunniest warmest spot so I'll leave them alone.