Taking ownership for Successes & Failures

My job experience has now been almost 4.5+ years. Most of it has been in the IT industry offcourse. Right from my initial years upto now I find one thing that has remained unchanged..... guess what ? Most of my colleagues as well as my seniors in my workplace, whether a small time company or the topmost company, always jump in to take credit for all achievements that me & my team achieves in the organisation. When it comes to accountability for failures its only me who is ready to take the burden. This attitude is prevalent right from my technical colleagues to my Managers. Though this attitude has helped me in achieving leadership roles much earlier than what other people do, it still sometimes bothers me. If you or your team do something marvelous & instantly take credit for the same then why don't you also hold yourself accountable for failures. We all are humans & not machines, & are bound to commit mistakes. Why does the saying "To err is human & to forgive is divine" stay only as a bookish knowledge & not realised in real life ?