Deflation generally benefits almost everyone. Things get cheaper and cheaper over time, while the amount of money you make stays the same. Technology is a beautiful example of this. Almost every year technology gets cheaper and cheaper, and better and better for the same amount of money spent. And of course this is great for everyone and I don't think many would dispute that.
Imagine a world where that wasn't true. Imagine you had to spend more and more every year just to get the same quality of phone or computer or TV. Now ideally, and depending on what's causing the inflation, your income would increase at exactly the same amount and so it wouldn't make a difference. The same quality TV would cost the same percent of your wage in 1960 as it would in 2013.
But with deflation it's the opposite. Your income will (on average) remain the same, since the amount of money in the economy hasn't changed and it's being divided over the same number of people. But prices will go down due to the economy growing, increasing efficiency, technological improvements, and all that good stuff.
You may see a slight flaw in my argument. Presumably the same amount of stuff is being produced in both economies, regardless how the currency is changing in value over time, and presumably there are the same amount of people to receive all the stuff being produced. So how can people in the deflationary economy be richer, on average, than people in the inflationary one?
Well on average, they aren't. Inflation as you are talking about it is caused by the money supply increasing. Usually due to the government printing more. Whoever gets the money first is suddenly richer, because prices haven't increased in response to inflation yet. The amount of money they have relative to everyone else has increased. Therefore everyone else has become poorer relative to them.
Only on average does everything stay the same, but it's a zero sum game where for one person to benefit, someone else has to lose. The amount of goods in the economy hasn't changed. But the person with more money (obtained through printing money) gets a bigger piece of the pie and therefore everyone else gets less.
Inflation is just a really confusing, inefficient, and indirect form of wealth redistribution. Whoever gets the printed money obviously gets to benefit from it, and everyone else is therefore poorer, including your entrepreneurs and investors and consumers and everyone else.
The only way this isn't true is if the money is distributed perfectly equally so the percentage everyone has is exactly the same as before. However this is not the case in the real world at all.