What are you calling a "low" open rate ?
Open rates are highly dependent on various factors (non exclusive list) :
- Market maturity for the products and services you offer
- Sender market shares and brand awareness
- Email object writing
- Market maturity for the subject addressed in the email
- Sender name and email address
- Specific maturity of the addressee in its purchase cycle
So, comparing open rates from one country to another, from one market to another within the same country is almost impossible.
I usually prefer to focus on rate evolution over time,