It's likely both:
- WordPress-specific bottlenecks,
- exacerbated by Host-specific configuration (in this case, GoDaddy)
A quick Googling shows that WordPress on Godaddy has a history of performance issues:
In the above forum topic, one reader mentions around 3900 websites all running off the same virtual host server IP – that's… a lot. Other posters mention larger-scale issues with MySQL performance with Godaddy hosted sites.
The following advice is also given (much of which is still applicable):
Things I've found that help on GoDaddy's shared hosting:
1. WP-Super-Cache. The hosting isn't as bad at static files.
3. WordPress 2.8 causes a rather dramatic dashboard loading speedup.
4. In GoDaddy's hosting configuration, change it to PHP5 instead of the default PHP4. PHP5 runs much quicker on their systems for some reason.
WP-Supercache, or any of the other reputable caching plugins, will make a huge difference in performance – cached static pages require no database access to load, so especially for Godaddy this should be a big performance win.
Other similar options, like using Gzip/html/css compression will also reduce the size of files that are downloaded, which will "speed things up" for browsers. Being able to use canonical URLs and expiration dates on all relevant files will make sure that they are only downloaded once and cached on the client side, rather than at every request/visit. Some of these features can even be enabled via plugins, if you don't have lower-level webserver access. For more on this, just google "wordpress compression", and read to your hearts' content.
Long story short, it sounds like hosting WordPress with Godaddy is neither the cheapest, nor the fastest solution… But as long as you're going to stick with them, you should definitely familiarize yourself with the above tools and plugins – they will assist you greatly, regardless of where you eventually migrate your site (highly recommended).