I am a firm believer that advertising is never black or white, that it is made up of infinite shades of grey from which it is impossible to ever get a completely correct campaign. Such a thing does not exist, and even if it did, that does not mean it would work or be taken to heart by the public.
From a planning point of view we can say 'has this worked?' or 'has this changed behaviour?', but we have to remember that advertising is both a creative industry and a sales industry.
What do they have in common? Neither have an answer that is perfect for everyone. No salesperson will have a patter that everyone responds to, not even the best in the world. Just as no creative will ever work for every single person. It's just impossible, we don't work that way as human beings.
There are great ads that have done extremely badly, just as there are good ads that have done unbelievably well. Sure media spend plays a part (Go sodding Compare), but there is never a guarantee that good creative means success.
In a perfect (hah) world Weetabix would be flying off the shelf right now and people would be buying car insurance from Compare the Market; while DFS and Gillette would be going bust.
Our job is to get as close to the theoretical sun as we can, both creatively and effectively. We should never try to be perfect as it cannot happen.
This is another reason why I believe in flexible thinking. If a creative has an idea that isn't on brief but is potentially better in ther ways, we shouldn't throw it away. Sometimes this even justifies post-rationalisation; if you have a random idea that is very good, should you spend another 3 weeks trying (and maybe failing) to get something a little bit better, or do you spend the 3 weeks making the current idea work brilliantly, and fitting it into a sound strategy?
Of course, having seen some clients holding full creative pitches at 48hours notice; maybe we all would get closer to perfect if we had more time... but we need to know when to stop searching and start developing.