No. If you check your account, you can see that "Steem" can be powered-up, and "Steem-power" can be powered down. Steem is tradable and volatile, but Steem Power is your voting power and protects you from dilution/inflation. If you lock up your steem by powering up, you have a long term interest in the success of Steem, which is why you are given power to influence (vote). If you power down, 1% of your funds will be released once every two weeks, so it will take you 2 years to fully empty your account. If you earn more by voting, a portion of your new funds will be automatically as Steem Power, which you will have to separately power down again. If you keep participating and bringing value, you will never be able to liquidate everything. You "can always check out, but never leave".