In my country during the year 2016, 8th November the government announced currencies with highest denomination like 1000₹ and 500₹ won't be valued anymore. People are supposed to reach the banks and exchange it to any other denomination. In the event of this people suffered much, because there is no money to spend and banks were full of crowd. More than 100 lost their live standing in queue.
Whats the reason for such an immediate decision ?
The government stated it a reason to fight illegal funding to terrorism and recove the black money.
If there is validity or expiry for every currency same as day to day life needs, then people will make use of it and exchange to new currencies at the right time. This way everything can be made to be in circulation rather than getting accumulated for years. Here black money can also be avoided.
Funny what the government thinks will work....I will tell you what really happened. I was back in India for 2 months and I live in a small village and there the people with black money paid like 50-100 Rupees to poor people to stand in the line and exchange their money.
This is literally what happened and the people escaped very easily. For them or was an amazing time to convert the black money into the white money.
Now I do think this didn't help much but maybe in some cases it did , but we cannot consider that a universal statement and start worshipping what they did. I did find it utterly useless since the government doesn't know how the local people works. Had it been known that this is happening it would have saved a lot of trouble for sure.