Why digital pin not reading ON from push button switches connected to 5V and pull-down 10K resistor?
when the switch on pin 4 is closed the stateDirection variable still reads 0, or open circuit.


you could have pull-up enabled on that pin: with a nominal value of 50k, 10k pull-down is just on the cusp of making it a logic low. 

solution?

1) disable pull-up;
2) use a stronger pull-down;
3) get rid of the pull-down and rely on the pull-up alone.
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