We don't "need" inflation. It is primarily a function of money supply which is usually a government function. Prior to the New Deal, inflationary spikes would be followed by deflation and prices did not really change much in the long term. As the US government grew, inflation became a more constant pressure. Increased government spending puts upward pressure on prices. Part of this comes from the concept where government departments spend 100% of budgeted money (or more, rarely, if ever less). A business will look to reduce costs, especially in tough times. The government approach is that if Congress appropriated an amount of money, it would be inappropriate to spend less. This flies in the face of common sense.
Example: Congress appropriates $30k for a new tractor. Bureaucrat A makes a good deal with a dealer and gets the necessary tractor for $20k. Bureaucrat B has been doing this longer and either doesn't negotiate or just gets another $10k in superfluous upgrades. Bureaucrat A is reassigned to lesser role for failing to spend the appropriated amount. Bureaucrat B is hailed and/or promoted for spending all appropriated money. This system leads to more waste, corruption and contributes to inflation.
In business, you see the same example, but the manager who came in under budget is promoted and the other guy is eventually fired for incompetence.