Very true. I've had people look at my ~50% open rates and think they were low.. but they were sending product updates to a dedicated list of people who wanted to learn about that product. And it's easy to look down on e-commerce folks getting 10-20% but.. they're sending mails every day and making 6 figures a mailing, etc.
It's so contextual it's ridiculous. Stats from companies like MailChimp try to break things down by 'industry' but it's still not all that useful to compare against. The type of mail is just as important (industry news, personal announcements, product promos, sales, etc.)
Here's a chart of stats by industry that MailChimp published -
http://mailchimp.com/resources/research/email-marketing-benc...
for reference. As petercooper said the industry isn't the best breakdown to compare against. It's probably more helpful to benchmark your own campaigns using A/B and optimize for your goal.
To me, one big driver of whether I will open unsolicited mail is how often that sender sends something out. If I am getting email from you 3 or 4 times a week, it's almost guaranteed to be going straight into the trash. Not only am I not opening it, I'm not really even reading the subject line.
Once a week is borderline. Once a month is probably about right. Don't abuse your subscriber's time.
I'm on an email industry mailing list, and it seems big brands with giant lists are getting 1 - 5% opens and are really happy when they get a .5% increase on a newsletter.
It's so contextual it's ridiculous. Stats from companies like MailChimp try to break things down by 'industry' but it's still not all that useful to compare against. The type of mail is just as important (industry news, personal announcements, product promos, sales, etc.)