When you hire a Designer to produce graphics or presentations for you,
you're not looking to pay for a pretty looking thing;
what you want is work that fulfills it's purpose.
The mediocre designer churns out the most colourful looking thing that does not do it's job, and has a bulk of 'experience' doing so.
If you're looking to avoid that, hire a well though designer who knows how to siphon attention to what you want.