When viewing the step graph and some other similar graphs when grapg view the start of the Y axis isnt 0.
Therefore when looking at a weeks, months or years data days may seem like they have had loads more steps than a previous day as the scale is off.
An example is on this chart on Thursday I did 3,500 steps but on Friday I did 7,000 steps.
However as the graph doesnt start at 0 it looks like I did barely any steps on Thursday and then about triple the steps on Friday.