Monero uses three different privacy technologies: ring signatures, ring confidential transactions (RingCT), and stealth addresses. These hide the sender, amount, and receiver in the transaction, respectively. All transactions on the network are private by mandate; there is no way to accidentally send a transparent transaction. This feature is exclusive to Monero. You do not need to trust anyone else with your privacy.
IMO, as a software engineer, leveraging the network effect of Monero was a wise choice. In decentralized systems, the network effect (the amount of unique, separate nodes on a network) is directly correlated to the security of that network. If I were to transact with you in a public place (like a mall food court), you could correlate the presence of other parties in the food court as unique nodes in a network. The more eyes you have witnessing you transaction, the more intrinsic security that transaction has.
Another concept that actually comes into play in cryptocurrency-based systems is that the intrinsic value of that token directly relates to the security of the data in its network. That could be another reason that they chose Monero. Since it already has stable value, it offers a pre-existing and stable security solution.