The link you provided is wrong. The correct one is:
http://www.coindesk.com/short-guide-blockchain-consensus-protocols/The guide is informative, but unfortunately has some severe errors. The PoS paragraph only seem to describe the NXT protocol and similar approaches where the stakers only receive the transaction fees, but no variants with continuous minting of fresh coins (like PPC and the extreme cases of Hyperstake etc.), which are very popular in smaller cryptocurrencies.
And for Proof of Burn, the only implementation I know does not let the burners earn a "lifetime privilege" but a privilege that decreases over time and lasts one year as a maximum (At the end, they mention it: "Over time, your stake in the system decays"). And the sentence "the protocol still wastes resources needlessly." is simply false because in PoB no physical resources (only "virtual" ones) are wasted.
So unfortunately the guide has several inaccuracies and stays superficial. That may not be important if you want to get a first impression on "what's possible" but for advanced users it reads pretty odd.