When new money is injected, there are always first recipients of the newly-injected money who benefit from this injection. The first recipients, with more money at their disposal, can now acquire a greater amount of goods while the prices of these goods are still unchanged. As money starts to move through the economy, the prices of goods begin to rise, unevenly and disproportionately. Consequently, late receivers of the inflated money realize costs from the monetary injections and may even find that most prices have risen so much that they can now afford fewer goods.
Artificial increases in money supply generate a redistribution of wealth from later recipients, or non-recipients of money, to the earlier recipients. Obviously, this shift in wealth alters individuals’ demands for goods and services and, in turn, further alters the relative prices of goods and services. Inflationary increases in money supply set in motion new dynamics that give rise to changes in demands for goods and services and to changes in their relative prices. Hence, increases in money supply cannot be neutral.
You can see that price stability does not exist in general society with your own eyes. For instance, the dollar price of BTC keeps changing due to increased supply of dollars vs. BTC. Another example would be the change in the prices of computers in terms of dollars, there is in increased supply of computers, even as the supply of dollars increases!