Positions of PS pixels in mountainous area

Dear all,

I have processed Sentinel-1 SAR images using SNAP and StaMPS in a mountainous area. In some cases, I noticed that a few Persistent Scatterer (PS) pixels are located within a forest or on a road adjacent to the forest (indicated by the red arrow). However, the position of a nearby house was not selected as a PS pixel (indicated by the blue arrow). I am not sure why this is happening and would greatly appreciate any assistance or insights on this matter. Additionally, I would like to know if the PS pixels indicated by the red arrow are considered reliable.

Thank you very much for your help!