I can't speak for every elderly person because there are plenty that are great drivers.  I'm speaking basically about certain ones.  Let's start off by classifying elderly as over 65.  Take for instance my dad, before he passed away at age 75 was a safe, very good driver that just drove slow and would never take the interstates because, in his words, "I'm not as good as I used to be and I get nervous with all of that".  Then, take my mother.  I would white knuckle riding with her.  She would break almost to late, drive way to fast and always drove on the aggressive side.

My mother-in-law is mostly the kind of driver I'm talking about.  She's that driver that tries to be extra safe by doing things that are not so safe.  She'll make a wide turn because she doesn't want to hit the curb but not pay attention that she's crossed the lane.  Or she'll want to make a turn and forget that there are other factors to think about.  OR, she won't pay attention to both sides and at one point, hit a parked car.

Lately she's gotten better but needs a lot of work on her parking, as you can see from the picture.

She tried.  She really did.  I just think that maybe it's time to take a test.  Or maybe that's to harsh, a refresher course might be a better solution.

For now, I'm going to hide....probably NOT in my car next to my mother-in-law though.