You talked about bank account, but people usually have much less money in their bank account than what they earn in salary. And with a deflationary currency, the value of your work declines year after year in that currency, meaning that your employer will be willing to pay you less and less every year!
As long as inflation is low enough, people don't really care about it in general because there salary increases as much (and given than the average American has much more debt than saving, the inflation is actually a gift to them).
So I talked about workers, but how about investors and entrepreneurs? Say I have $10 million today sitting in a bank account. I can either let it sit idle, losing value to inflation every year, or invest it somewhere where it can create value. Now if the value of my $10 million increases in real terms (meaning that my purchasing power will naturally increase when time passes) the most rational thing to do is not to invest that money. It's actually unlikely that my investment will pay off anyway, because the amount of money spent by people will decrease year after year (because that's what deflation means).
The idea that deflation is better than inflation (or, more broadly, that inflation is undesirable for the consumer) is libertarian ideology that I reject.
