Tell me if I have this right - New coins given as interest will require 24 hours to mature, so total simple interest rate after 7 days of compounded interest will be 17.71561% less.
This is what would happen if there was no waiting for maturation:
7 Day simple interest rate after compounding at 10% daily = 94.87171%
Day | % |
1 | 10 |
2 | 21 |
3 | 33.1 |
4 | 46.41 |
5 | 61.051 |
6 | 77.1561 |
7 | 94.87171 |
With waiting for maturation:
7 Day simple interest rate after compounding at 10% daily = 77.1561%
Day | % |
1 | 10 |     1st day new coins are immature. |
2 | 10 |     1st day new coins mature, added to interest calculation |
3 | 21 |     2nd day new coins mature |
4 | 33.1 |     3rd day new coins mature |
5 | 46.41 |     4th day new coins mature |
6 | 61.051 |     5th day new coins mature |
7 | 77.1561 |     6th day new coins mature - so not included in compound interest calculation (@ 10% daily simple interest)
|
So if it works then you have to wonder at what point people are going to bail out and cash in their chips

And if price will decrease greater than interest received...
no , it doesn't work that way. PoS is not exact timing. PoS is mining. The timing is just estimate. Its not the exact time. Sometimes it takes longer sometimes shorter just like pow. It depend on luck. One of your block stake interest at 1pm today doesn't mean the same block will get stake exactly at 1pm the next day.