IIRC deflation and inflation are equally as bad. If 'inflation' rates are negative, the economy grinds to a halt. Having an inflation rate of ~2% is widely considered to be beneficially for everyone, since it's in a 'goldilocks' zone, it creates stability.

Inflation of 4% sure isn't as good as 2%, but generally speaking the inflation rate in the UK appears to hover around 2-3% during "stable" periods. https://www.macrotrends.net/countries/GBR/united-kingdom/inf...