The languages aren't so bad, but the ecosystem is rough. On the PLC vendor side, implementations vary widely and they're all proprietary, so for a given control

The languages aren't so bad, but the ecosystem is rough. On the PLC vendor side, implementations vary widely and they're all proprietary, so for a given controller... what they give you is all you get. On the programmer side, skills vary widely and ladder logic is the common denominator, so a lot more is written in ladder logic than is appropriate. For instance... Complex sequential logic (like a machine with many adjustable operations, all controlled by an HMI) is difficult to convey clearly in a ladder logic program. It can be done... but all I have ever encountered is lots and lots of spaghetti logic. I wish I could use sequential function charts to handle some of the complexity in the machines I work on, but the PLC models we use don't even support them. Argh.