In defence of; never taking your own advice.
"Take my advice - I'm not using it!"
But also, I think it goes back to that idea of how unkind we can be to ourselves. We have those voices in our heads that say things to ourselves that we would never say to a friend. Some day's I can stand there and look in the mirror and say 'I look shit today' or 'I really need to get back to the gym' or, on really bad days 'I'm terrible at everything and I'm never going to get anywhere in life'.
Can you imagine saying that to a friend? I'm not sure they'd be your friend for much longer tbh, so why is it okay to treat ourselves like this?