I know the /s but I also want to introduce you to amorphous solids! (Because I like them so now you get to read this lol) https://en.m.wikipedia.org/wiki/Amorphous_solid

Which is essentially a "solid" structure without a proper crystalline structure. This will cause it to move as a liquid at incredibly slow speeds. Such a glass for instance. Extremely old historical glass can be seen to be thicker at the bottom than the top. Not because it was built this way, but because over hundreds of years it has "poured" down [1].

*This is a simplified explanation and therefore may not be acutely accurate for sake of simplicity

TL;DR Some solid stuff is really just super slow liquids. I.E. Glass

[1]: See link in comment reply. Glass is an amorphous solid but sources say that glass pane construction is the cause of thicker bottoms rather than it's movement over time.