Welcoming Ukraine to become a properly confirmed member of NATO would show Russian Pres. Putin that his aggressive and illegal actions in the country are undermining Russia's credibility on the geopolitical stage. As Ukrainian Pres. Zelenskyy has said, Russia must recognize that Europe has borders and independent states, and that every sovereign nation has the right to choose its own future.
Dragging Ukraine into the NATO military alliance is what started this whole conflict in the first place — particularly NATO's cultivation of Ukrainian nationalism that resulted in a violation of rights against the country's Russian-speaking citizens. Without eliminating the root cause of the conflict, it's impossible to achieve a fair settlement.