We used to have lots of broad match keywords and the click ratios were all low, 1-2% and less.
However we had a lot of branding exposure (not clicks) to a wider range of people who might learn to associate the brand name with the type of products we are selling.
Then there was the optimal ad design for saving money, the one that just says :
widgets are us,
all types & colours
tel: 0898 362 348
Which if course is not permitted by google :-) sadly.
Anyhow, now I have tightened the keywords by making most of them phrase match, our exposures have gone way down and our clickthrough ratio is way up.
But what about it, is there a branding effect of higher exposures which one loses by focussing keywords?