Advanced Persistent Threats are able to slip past even the most cutting-edge security defenses thanks in large part to a diabolically clever strategy. The time an APT breached a system to the time it was detected could be anywhere from six months to a year or more. We found that in order to deploy these products successfully, security professionals must change the way they normally think. These threat hunting tools are not the passive observers that were accustomed to, simply reacting to alerts triggered in the SIEM. Instead, these are aggressive hunters who prowl their own networks looking to prey on APTs and undetected malware.”]
Source: https://www.csoonline.com/article/3151788/review-threat-hunting-turns-the-tables-on-attackers.html