Even though only myself and high reputed trusted users can see it, this situation (keeping deleted user entries without his/her consent) is not desirable in the internet world.
Actually, many "delete" buttons on the Net are only soft deletions. Fact is, they don't want you removing valuable content at whim.
(keeping deleted user entries without his/her consent
You gave consent by accepting the ToS:
You agree that all Subscriber Content that You contribute to the Network is perpetually and irrevocably licensed to Stack Exchange under the Creative Commons Attribution Share Alike license. You grant Stack Exchange the perpetual and irrevocable right and license to use, copy, cache, publish, display, distribute, modify, create derivative works and store such Subscriber Content and to allow others to do so in any medium now known or hereinafter developed (“Content License”) in order to provide the Services, even if such Subscriber Content has been contributed and subsequently removed by You. Subscriber warrants, represents and agrees Subscriber has the right to grant Stack Exchange and the Network the rights set forth above. Subscriber represents, warrants and agrees that it will not contribute any Subscriber Content that (a) infringes, violates or otherwise interferes with any copyright or trademark of another party, (b) reveals any trade secret, unless Subscriber owns the trade secret or has the owner’s permission to post it, (c) infringes any intellectual property right of another or the privacy or publicity rights of another, (d) is libelous, defamatory, abusive, threatening, harassing, hateful, offensive or otherwise violates any law or right of any third party, (e) contains a virus, trojan horse, worm, time bomb or other computer programming routine or engine that is intended to damage, detrimentally interfere with, surreptitiously intercept or expropriate any system, data or information, or (f) remains posted after Subscriber has been notified that such Subscriber Content violates any of sections (a) to (e) of this sentence. Stack Exchange reserves the right to remove any Subscriber Content from the Network, re-post to the Network any Subscriber Content removed by any Subscriber or former Subscriber, suspend or terminate Subscriber’s right to use the Services at any time, or pursue any other remedy or relief available to Stack Exchange and/or the Network under equity or law, for any reason (including, but not limited to, upon receipt of claims or allegations from third parties or authorities relating to such Subscriber Content or if Stack Exchange is concerned that Subscriber may have breached the immediately preceding sentence), or for no reason at all.
Paraphrased with legalese removed:
Whatever you write on SE is practically owned by SE. It is still attributed to you, and is protected by the CC-BY-SA license. Removing content does not change this, SE still has all rights over it, and can do whatever it wants with it.
Basically, the "delete" button is "please hide this from the masses".
If you have placed sensitive information in the post, you can always ask a dev to get it removed. Email
email@example.com. Or flag the post for mod attention, asking for it to be removed.