The TL431 programmable shunt regulator is a useful 3 pin chip that I use a lot. In a recent project I used it in the heart of a constant current circuit. I chose the symbol TL431DBZ which uses the SOT-23 package. Most likely I initially designed the board for PCBA and later decided to hand assemble it and use the TO-92 package. I thought it wouldn't matter since I would change the footprint to the TO-92-wide footprint. Of course I was mistaken. Here is the pin table for the TL431DBZ.

And here is the pin table for the symbol I should have chosen, the TL431LP:

Notice the pin number assignments differ. The result was that the pads in the TO-92-wide footprint weren't the electrodes I was expecting.

Fortunately 3-pin TO-92 packages can be rotated to give a different permutation of the pins and this is the hack I will use for the existing boards. The KiCad project has of course been updated.