Dumb in the sense that it should be common sense that excess of everything is bad. The same goes with your smartphone's battery life, of course it's not a good idea to keep it plugged in for hours even after it's fully charged.

A lot of people are under the assumption that once it hits 100%, the charge stops.

It seems I may have the jumped the gun too soon as all those disagrees on what I stated above only proves that people were not dumb only "till now".

I guess they still are.

EDIT - ( Don't know why my comment has been marked as inappropriate when there's a healthy discussion going on here ? )

I don't think there's any getting away from the fact that this a design fault.
As I said previously the most convenient time for most people to charge their phone is whilst they are sleeping (when they don't need it).
If leaving a phone charging overnight is significantly detrimental to the batteries lifespan, then this needs to be addressed by the manufacturers, or perhaps it's an idea for an app, if there isn't one already.

When do you find it most convenient to charge your phone?

Devil X Spends his whole day looking at this phone charge. /s

According to the article:

"Once your smartphone has reached 100% charge, it gets "trickle charges" to keep it at 100% while plugged in. It keeps the battery in a high-stress, high-tension state, which wears down the chemistry within."

Pretty dumb for a 'smart' phone!

EDIT - ( Don't know why my comment has been marked as inappropriate when there's a healthy discussion going on here ? )

Calling people ignorant and dumb is a healthy discussion? Lol.