Things in trapways
Unless you have a Caroma toilet with a 3" or larger trapway, you can't flush down potatoes, bars of soap, toy cars, toilet paper holders, shampoo bottles, doggies throwing balls, army men, cell phones, playing cards, carpet strands, coffee cups, construction waste, tile grout,
Heck, even the Caroma has a hard time with tile grout.
Carpet adhesive, measuring cups, pencils, car keys, I can think of lot's of things that kids and dogs drop in.
And construction workers.
One job I was one, the tile setter used the toilet drain to dispose of his broken tiles.
We use a closet auger with the large 1-3/8" end on it.
Smaller cables can go right by the obstruction and not move it.
We had a similar job we went out to, the first plumber told the homeowner that they had a defective bowl.
Jamie went out with his auger, and decided to pull the bowl.
This is what he found.
The first plumber had run his auger through, but it went right by Mr GI Joe.