Do you really have to shoulder check every 5 seconds?

Uh NO!
Just shoulder check when changing lanes.
constantly checking the road. mirrors, and other things but just shoulder check when changing lanes.

Only if you have a reason to need to shoulder check, and your need lasts 4 seconds since the last time you checked. e.g. you’re trying to merge but can’t do it right after you check, then check again before you do, in case there’s a speeding bozo zooming up from behind.

How will you be look at the road ahead if you’re looking back every 5 secs? It’s not about fun but practically not possible or advicible thing to do.

I have a (temporary) neck injury right now. I get pain in my arm when I turn my head even slightly to the side.
While driving to the doctor I noticed I was constantly, silently saying “Ow” to myself because I involuntarily turned my head to check mirrors and verified when making lane changes on a busy road. . Ow… ow…. ow….. 5 – 10 seconds was about right. Ow….

No, only when changing lanes. But I do keep an eye on the rear view mirrors.

@RedDeerGuy1 If you are considering getting a drivers license take lessons?

@RedDeerGuy1 And take a course in defensive driving!

@SQUEEKY2 I am not ready to drive. I would prefer a motorcycle or electric bike . Maybe a normal bike.

Even if it a normal pedal bike LEARN the rules of the road, use your hand signals to show others your intentions of turning right or left or coming to a stop.
If you are going to use it at night make sure it has lights and wear bright clothing so motorists can see you.