There is a lot of confusion as to how to get good ADXL graphs. For many, the issue is printer build and rigidity. For others, there is often an issue with ADXL mounting or noise. Like all of my guides, this is targeted at people chasing the highest performance with quality. If your quality and speeds are fine for you, stop reading as this guide isn't for you.
There are a few parameters that play into your measured values and this will break down the most straightforward. Broadly, they are mass and stiffness. This explanation will not be true in every single instance, and is definitely not PhD level physics, but should at least help with the broad understanding of what your printer is doing.
The easiest way to think about it is if you start by thinking of your printer as an undamped simple harmonic oscillator.
