in my understanding, the persons to be told is a safeguard for the person giving POA. In the event that the POA is activated, these people are told that it is being activated. So for example. my mum and dad have nominated me as their poa, but it remains unactivated as they both have full capacity. When it is activated, my sister is one of the ones to be informed. This prevents me from registering it and selling their house or clearing their account for example cause she's bound to think "why has she registered it?" and ask them