Delegated Proof of Stake is different in security aspects related to blockchains because of the use of a delegation system where the token holders elect a small number of delegates that validate the transactions and maintain the network. The list of advantages and vulnerabilities assigned to this consensus algorithm is enormous.
Efficiency increases with DPoS because the number of validators is limited, so therefore it can much more quickly process transactions and thereby create more blocks. Security for DPoS is provided mostly by means of economic incentives and accountability. Delegates who behave in a dishonestly manner or without doing their duties will be voted out and changed; hence only honest participants retain their positions. Election forces these delegates to act honestly not to lose their status and rewards.
However, DPoS faces a heightened risk of centralization whereby a few powerful delegates dominate the network. In the event that these powerful delegates collude, then they may compromise blockchain security and integrity. Centralization can also be exacerbated when there is a lack of voter participation-that is, fewer token holders will vote.
In general, while DPoS is secure due to dynamic election and incentive mechanisms, high decentralization and active participation by its community are very important to avoid centralization and provide long-term security to the network.
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~ Nesaty