selection context breaks on long inputs?

[Behem07h]

I'm really confused why this is happening, if i test it on a smaller input like below it works as expected
test

• test
• test

the problem text:
supposing you can do a probe accuracy test (and for anyone else reading)
• if your z axis repeatability is the issue, you will see an increasing standard deviation as you increase the probe test count. this is because the test does not home between probes samples, so your tracked position slowly drifts from the actual physical position
• if your z axis is experiencing stiction in the movement, you will see a decreasing standard deviation as you increase the probe test count. this may happen if excessively thick lube is used and the first initial movement from rest encounters higher resistance
• if your probe has accuracy problems, the standard deviation should remain relatively constant