Inflation is bad to the extent that it causes the total stuff we produce to go down or to become more poorly distributed, and good to the extent that it does the opposite.
And a shrinking of the pie - a reduction in stuff produced - can/will cause inflation assuming people have the same or greater amount of money with which they can purchase that stuff.
The more we stay focused on the production of stuff, and less on the quantity of money or inflation, the better off we will be, and inflation will take care of itself.