For Susanna Reid it makes sense. Presenters (particularly female presenters) are often "hot" enough to spark a bidding war only once in their careers. She's going to get paid a lot more money, avoid a lengthy travel to Salford and she'll be the Queen Bee, with ITV building a whole show around her. No doubt ITV have included a clause that involves them finding her primetime work as well.
It's a lot of money for a breakfast presenter but at this point ITV's need is greater than the BBC's so they'll pay up as required. I struggle to see this working out particularly well, Breakfast has a massive lead, but I don't watch breakfast TV and never have so I'm not exactly an expert in the area!
From the ratings it just seems that every revamp costs them more viewers. Perhaps they're betting on a new brand generating some interest but wasn't that the original pitch for Daybreak? And yet looking at the recent Daybreak ratings, they kind of have to take a swing at a re-brand, even if the odds are that it won't work. Because the status quo isn't working either.
And I think there could be a lot more than Helen Warner's job riding on this! I wonder if this is the last swing at breakfast for ITV? If this doesn't work out then what next? How many brands, producers, commissioners, presenters... will they try before they think it's a lost cause and give up?