Daggers... Whats the point??

So I've been making up my new PC and I wanted him to be a more combat-shy person who has just a small knife on him in the case that he needs to defend himself. In my building, however, I got to thinking. What benefits does taking a dagger have?? From what I can tell the only major benefit is that it costs almost nothing to use one but that's it. I know that in other organizations the dagger is useful because "Waylay" can only be performed with a dagger, making them fill a niche role that rogues and sneaky types can capitalize on, but seeing as waylay doesn't even require a weapon to perform, I'm struggling to find a justification for holding onto a dagger after early levels instead of a sword or something. I'm happy to be proved wrong, but from what I can glean I got nothin'.
I only have short weapons. Can't say there's an advantage to it other than that's what my character prefers to use. So it's more of an RP thing than anything else I suppose.
They can be used to cut people free from "physical" entanglements (ropes, webs, etc.)
Yeah, it can. But, take for instance, the cost of a longsword versus a dagger in build spent for a scholar. *shrug*

As a fighter or a skirmisher rogue, you can keep one around with a weapon coating on it for when you need to deliver a status effect. But in general, you're correct; Daggers end up filling very niche uses and not much else.
I don't think you need proficiency to cut a rope, only to block or deal damage.

Could be wrong tho.

Rocks and arrows are better for applied poisons. Daggers are complete garbage for everything aside from roleplay.
Rocks and arrows are better for applied poisons. Daggers are complete garbage for everything aside from roleplay.

Unless you happen to play a race that can neither use a bow nor throw a knife!
The point of it is to thoroughly and utterly demoralize your opponent by besting them in battle with a single dagger against their weapon(s) of choice.
I used to always keep a minimum length dagger hidden in my armor just in case I was searched by someone like guards or had to be "empty handed" to a attend a meeting.

Sometimes weapon length us an issue, say when you unexpectedly find yourself crawling through a narrow sewer tunnel. (I've been in that unexpected situation chasing a bad guy and my polearm wouldnt fit and didn't have an opportunity to get an alternative weapon; glad I had my hidden dagger with me though)