I mean never. Constant vigilance, otherwise you'll find yourself banging your thick skull against a brick wall instead of doing the Happy Dance of Success.
We're all told (and if not, then we're bright enough to figure out) the importance of stalking-- I mean researching-- agents before sending queries. Showing that you took the time to comb the internet and get to know them before querying them means you, at least, actually feel you're a good fit. You didn't eeny-meeny-miny-moe them or pick their names from a hat. Yes, research the agent, research the agency, make certain to send all the materials they request (and be careful to send no more than they want). That's the author's responsibility, and it's crucial to being taken seriously.
What they don't tell you on their websites is that their carefully-listed response time is apparently just a guideline. Now... don't get me wrong! I am not (absolutely not) criticizing. An agent's job is difficult, time-consuming, and her work load is probably unbelievable. I know why it takes agents four weeks just to say, "Howdy." Four weeks, six weeks, eight weeks... the more popular the agent, the longer it takes her to wade through the slush pile and return a polite email rejection suggesting your work is surely wonderful but not her cup of tea.
No, I'm not criticizing, I am only here to warn fellow authors of what we should know anyway. If I'm beating a dead horse, you'll forgive me. But maybe we all need reminding every so often, anyway: check your email at least three days a week if all your queries haven't returned rejections. Yes, even if the agency or agent promises a response within four weeks and it's been twelve. Check it. Keep checking it. Constant vigilance. Never assume lack of response is a rejection...
I sent out the last of my Round Two queries in mid-February. By early May, I still lacked responses from two Round One agents, and one from Round Two. I was at the stage where an author must choose whether to re-query (aka "pester") or write off. Typically, an agency's website or an agent's profile will tell you which is warranted, so the first thing to do is check. One of these said, "If you don't hear back from me within eight weeks, you can assume you've been rejected." Nice. Not even a, "Thank-you, no." That's all right. The second suggested that authors re-query if no response within twelve weeks. That's better, though I really, really hate seeming pushy. The third said "general response time about four weeks." I checked the calendar. Ten weeks. Very well, I told myself. It's time to re-query, but I'll just save it till I'm ready to send out Round Three.
I thought it was safe to ignore my email for a time. I had plenty to keep me busy: one houseguest after another (and the requisite cleaning), daughter's birthday party (the event of the year, around here, with 20-30 kids plus parents to feed and entertain), yard work, planting (making love to Mother Nature)...
Weeks passed, then on Friday Night Pizza Night (aka Mommies "Wine" and Kids Don't Night) by chance, my BFF asked a question regarding Gmail and Google+ so I fired up the old email... and nearly dropped dead of heart attack. There it was. "