I've mentioned before that when we moved into this house in November 2016 I panicked. We bought the house for the garden but once we moved in the responsibility of what we had bought finally hit. So I panicked and hired a local tree surgeon to come and prune everything into shape, thinking that unless I kept everything in perfect order I'd be evicted from the village. Of course, when I instructed them to prune what had been pruned previously into a similar shape, I had no idea that some of the trees and shrubs might not appreciate being pruned in November. My only experience of pruning up until that point had been some soft fruit bushes and an over-enthusiastic American Pillar climbing rose; these pruning schemes are not universal.
The sacrifice for my lack of knowledge was the beauty of some spring blossom, particularly on the spiraeas and forsythias. But I learned my lesson and once I'd seen them in (diminished) bloom and figured out what they were, I pruned them at the right time (after flowering).
The reward for correct pruning was breathtaking and I don't think there was anything in the garden that gave me as much pleasure at the spiraea arguta this year.
When they say do nothing in a new garden until the first year, listen.