Unless I say I've added them to give others ideas, I'll have tried over 90% of those posted by me. Often they'll have been entered in some sort of competition, with the usual rule that copyright is signed over(no longer mine). Standard in most competitions, which is where they'll get their recipes for any publication they make. Cheap and easy method.
Some have been my own creations, from scratch, not adapted recipes because the origional was meant for four, whilst mine serves less.
What I got fed up off, was posting my own or relatives recipes, then have someone say "it looks identical to this one" they've found on the internet, why haven't I linked it? The same can be said for those "adapted recipes". Why are they not credited?
I've seen adaptations in size of relatives recipes, with no accreditation given. I've just let them know. In the worst case, someone bought a book to check what I'd posted.
There's times when it's liquids only for me. Hence the smoothie recipes.
I've found it easier to link to the sites & recipes than to have someone search for it on the internet, then say mine is the "same as this".