NATO did that when Russia demanded that NATO not offer Ukraine and Georgia Membership Action Plans in 2008, complying with the Russian request. Russia responded almost immediately by invading Georgia, this is also a factor in why Ukraine, even after deposing Yanukovych, did not renew its bid to join NATO until after the Russo-Ukrainian War started with the Russian invasion in 2015. To quote a famous American statesman: “Fool me once, shame on you; fool my twice... can’t get fooled again.”
> (remember that NATO membership means eventual bases in Ukraine, and questionable status for Russia's lease on Sevastopol)
No, it doesn't mean foreign bases in Ukraine (not all NATO members have foreign bases), and Russia's invasion on 2014, largely carried out from and in violation of the agreements governing the bases it had in Ukraine, pretty much guaranteed that their use of those facilities was gone if and when Ukraine regains control of Crimea.