12+ Hours:
That’s half a day. It’s doesn’t mean you’re 100% unimportant, but you’re definitely on the cusp of insignificance. In 12 hours, Nick Jr. turns into Nick at Nite, breakfast turns into dinner, and Instagram goes from #RiseAndGrind posts to a bunch of sunset photos. Surely a measly text can be sent sometime before SpongeBob evolves into Friends reruns, right?
One Full Day:
If the person you’re waiting to hear from isn’t some free spirit, hippie type who may’ve been out of cell phone range for the past 24 hours, then you just aren’t a priority. In fact, you might even be a pester. They’re either dropping phone reception or dropping hints, and it’s pretty important to identify the difference.
2 Days:
It takes 42 hours to drive from Los Angeles to New York. If someone in LA who cares about someone in NY could literally drive all the way to see them in the flesh before you can get a text back, that should tell you all you need to know about how remarkably low on their list of priorities you are.
1 Week:
This is how long super lazy people avoid doing dishes. So yeah, conversation with you is the equivalent of a sink full of dirty dishes. They finally responded for the same reason you eventually wash a crusty bowl – because you might need it again some day.
2-3 Weeks:
Step 1. Find a self-help book about only being involved in friendships/relationships in which your presence is valued.
Step 2. Have it sent via UPS Ground or whatever the slowest shipping option is. It’ll arrive in a week, tops.
Step 3. Take the spare week(s) you’d still have left until you get a response to read the entire book, and by the time they text back you’ll know just how borderline offensive a multiple week response time is.
A Month (Or Longer):
The only feasible explanation they could possibly be throwing your way is the classic “omg I JUST now saw your text!” You don’t “just now see” text messages from people you want to hear from, several weeks after they were received. Are you important to a person who takes 8.33% of the year to respond to a text? As the brilliant Angelica Pickles once said, “If you have to ask, you’ll never know.”
However long until they unexpectedly run into you and are all like, “Oh, dude, I totally forgot to text you back that one time.”
You and your text messages are like a fly at picnic or a pesky Adobe Update popup, and they have zero interest in hearing from or responding to you. The day you run into them is like when your computer finally forces you to upgrade to the latest Adobe Flash Plugin. Their fake kindness during face-to-face interaction may make it appear as if they meant to download your newest version, but I assure you they didn’t. Don’t text them anymore. Be better than Adobe Flash Player Updates. 
