system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why do different people poop at different frequencies? Where does the waste go for people who don't poop often?

I apologize in advance for this gross question. But I poop 2-3 times per day, and my wife poops 1 time per WEEK! I don't get it, is her body just better at getting all nutrients out of her meals and thus making less waste? Is her colon packed out like a Jersey shore club on a Saturday night? Why? 

Plus when she does poop its some little nugget dudes, as opposed to my soft/wet mess (again I can't apologize enough about this post). Is that a factor?
gpt
Here are a few factors that determine one's bowel movement frequency:

* Diet (esp. fibre)

* Fluid intake

* Gut motility

The last one just means "how enthusiastically your gut pushes stuff along." It does vary from person to person, so someone's "normal" might be once every few days where another's (like you) might be frequent. It's also affected by medications, like laxatives and drugs that constipate you as a side effect. 

Poop that isn't pooped out just collects in the colon; that's really the colon's job (in addition to some water absorption). As long as it stays there, it gets harder and drier. So yes, someone who poops less frequently will have a harder time of it. From a doctor's perspective, the ideal bowel movement just comes out when you're ready, rather than needing any straining at all.