In addition,

- you cannot park here on such and such time for street cleaning.

- you cannot park here on such and such time for rush hour

- you cannot park here on such and such time for snow removal.

Plus there are license plates that are sometimes given permission to illegally park based on the reasons not to park.

- you cannot park here during such hours without a permit

- (unsigned, city-wide bylaw) you cannot park anywhere during such hours without a permit unless otherwise indicated

- (unsigned, city-wide bylaw) you cannot park anywhere for more than 3 hours unless otherwise indicated

- you cannot park between the signs (taxi stand/pickup)

Also:

- no stopping anytime

- you can not park here on school days

- handicapped parking only

- commercial loading only

Also!

- 3 minute passenger loading!

- Taxi-only parking

- Ambulance waiting spot

All of these spots are also "idling police car" spots.

Also!

When a sign serves to delineate areas with certain rules using arrows (e.g. no parking past this sign).

In addition:

- Parking for loading/unloading only

- You can park anywhere on this block for a cumulative 2 hours per day.

Those three examples are only different in the reasons given for the time-frame. You don't need to provide reasons, they're irrelevant, someone who wants to park somewhere cares whether it's illegal or not.

... and street cleaning is on the 2nd and 4th monday of each month (got towed on that premise once)

What is it about US streets that makes them so much more filthy than other streets that they not to be fully vacated in order to clean them sufficiently?

The only example for "irregular" no parking times I've seen in Germany are special exceptions for markets (typically Wednesday and Sunday, but the sign won't tell you if the market is cancelled on a particular day for a particular reason and you won't get towed or fined if you then park there when the market isn't happening) or special occasions (e.g. a circus) where they put up a temporary sign a week in advance.

I guess Germans really are more efficient (while simultaneously being more in love with having rules for every eventuality).

up nord : - you cannot park here on even days from Dec 1 - April 1

Agreed. Of course, we can now argue whether this level of granularity is unnecessarily complicated.

However: it's hard to argue that the three cases that I listed are too many rules, yet it's easy to see that they can cause too many signs using the OP's design. Such a simplification made the point much clearer, but I should have made that explicit.

Electronic signs.

- Free parking (5 hours remaining) - No Parking (4.5 hours remaining)

Of course, that has its own problems, (Power, vandalism, bugs ...) but it would help drivers a LOT. As the article said, no one cares about WHY they can't park, usually. It's only "can I park here right now?" that matters in most cases.

While true, the second most important thing is "can I park here for as long as I need?"

"Free parking (1h 45m remaining)" doesn't help if you want to park for 2 hours and don't know if the next time period is "no parking" or "max 1 hour parking".

The third most important thing is likely knowing about some time in the future, like "will my visiting friend be able to park here on Saturday evening?"

Actually, the time limit on paid parking doesn't necessarily mean that you can only leave your car in that paid space for two hours. it means you can only pay for two (or whatever) hours of parking at a time.

In the UK on-street parking for 1 or 2 hours usually has a "no return" period too.