Do most people receive no replies at all to their queries, or is it just me? I feel like 70% of my queries go unanswered. Is that a sign that I'm doing something wrong?
I've had a significant nonresponse rate, but not 70%. (How many queries are you talking about here? How long do you wait before you are assuming no reply?)
Some agents are simply nonresponders -- or frequently are. Have you looked at querytracker? I usually do that before I query in order to see if the agent involved responds and how quickly. (Sometimes agents' websites will also tell you that no response within a particular timeframe means "no.")
Also check out the AW threads for each agency. They might give you an idea of what is usual for a particular agent.
I suspect that as the number of queries have increased, the lack of answers have also. (Then, too, there are the people who write back arguing about the generic rejections they've received, leading some agents to become more nonresponsive.)
Try to hang in there. Then you can complain about the agents that ask for submissions and then do not respond
Anyway, if the agents that aren't responding to you usually do respond, it is time to see what might be wrong. You aren't addressing things to "dear agent" I assume or any of the other major no-no's? There's a place on AW where folks will critique your query.
It sounds obvious, but be sure to include a SASE for written queries and contact information in the body of any emailed queries. The last isn't intuitively necessary, but I've read of forwarded emails that lose the originating email address.
Don't take an agent's word that he or she always responds BTW. I've had a few folks who say they respond to everyone -- but they haven't to me. Maybe I'm special