low quality score

I'm looking at an old account that hasn't been worked on or active for years.
There was a couple of campaigns that were used, some with overlapping keywords, but geo targetted differently.
One targetted the whole of Wales and one targetted Cardiff

Now in the Cardiff campaign that I've solely reactivated:

1. The landing page is very relevant
2. The ads are relevant and have keywords in them
3. the keywords had the service e.g. web design in all matches

When I reactivated this Cardiff campaign, and added the service + city keywords, broad, exact and phrase match the issue that I'm having is that most of the new keywords appeared straightaway as 'rarely shown due to low quality score', and the keywords that were already in that campaign have a low quality score of 3-4.

Any ideas on what I should do?

thanks.

 

don't know exactly ?
good post can we use it for email campaigns?

 

This quality score mystery is still unsloved for me . I just have no idea how google determines QS,.

 

quality scores. So if, in the past, the account was not optimized well and therefore did not have good appreciation from the consumer, then Google could be down grading the quality scores for that reason