They managed to regain a bunch of territory early in 2022 because Russia lacked troops to defend it and sensibly chose to pull back. This became the basis for a lot of the mythology around Ukraine’s ability to push Russia back. This likely greatly contributed to the inflated expectations for the summer offensive last year. The west expected that Russia would just give up territory without much of a fight again, then they’d back Russia in a corner and force negotiations on western terms.
They managed to regain a bunch of territory early in 2022 because Russia lacked troops to defend it and sensibly chose to pull back. This became the basis for a lot of the mythology around Ukraine’s ability to push Russia back. This likely greatly contributed to the inflated expectations for the summer offensive last year. The west expected that Russia would just give up territory without much of a fight again, then they’d back Russia in a corner and force negotiations on western terms.