What's wrong with my echeveria?

[QuietKingdom]

Last spring/summer I moved my echeveria outside and one variety developed small brown spots on the leaves. I thought it had got sun scorched but they haven't gone away, more have grown and I've noticed the new growth has the spots too. Otherwise they've grown strong and healthy. The pictures are 3 different plants, all started as leaf cuttings a year ago so they're growing fast and strong. There's no insects or scale bugs that I can see, and it hasn't spread to any other variety of echeveria. Does anyone know what the problem might be? I can't seem to find the same thing on Google. I don't know if it's a pest/disease or something like too much/too little watering or too much fertilizer or something. I've only been growing succulents for about a year so am probably doing something wrong!

I suspect it might be a fungus causing the blemishes, but I'm not a great expert on succulents. You might need to look on a specialist succulent website to find out how to treat it.

Thanks I hadn't thought of a fungus, that could be difficult to treat then.

Possibly callousing over of physical damage

@MereDintofPandiculation thanks, do you know what could be causing the physical damage? The marks appear on the new growth as well as the older leaves.

One cause could be oedema - thesucculenteclectic.com/understanding-plant-edema-on-succulents/, little blisters of water that can appear on the leaves of succulents, sometimes caused by over watering. Make sure the potting mix is well drained, with plenty of grit, and only water when dry.

Thanks Nan that's great, that might be it as generally they look like healthy plants and are growing rapidly. I do tend to over water I think, perhaps I've just been lucky that it hasn't affected the others or this variety particularly likes to be dry. I hope that's it. I normally water about every 2 weeks but will make sure I leave it longer for them in future.