Harcoding items vs using a JSON database

Hi everyone,

I'm quite new to C# (and programming seriously as a whole with this) and I've been looking into building an inventory and item system for my game. A lot of people (that being everyone I've read/watched stuff of) seem to go for JSON's for this.

Now, honestly, I dont have a clue how this works and I don't really want to just copy what I see because I want to understand what I do. That said, what makes using a JSON database that you convert to items so much better of an option than making a prefab of every game item?

If what I typed doesn't make sense, it's probably because I really dont understand how JSON's and their integration/conversion works. If people could help me understand this, that would also be amazing.

Thanks for your time! Oh and have a great Xmas~