Because here's my thoughts on the signs:
1. These signs don't deter me from tailgating your bumper, while my own child sings "Let it Go" for the 1,000th time in the back. No, if anything these signs infuriate me. You had a child. Congratulations! But you know what, that sign was not issued by the DMV, nor was it given you to as you left the hospital with your newborn. In reality, the sign means nothing. Yes, you should be safe while driving with a little human, but don't put that sign up to mask your lack of driving skills. If you are slowing down for a yellow and driving twenty five through a neighborhood I'm going to call you a name and possibly give you the finger. Own your bad driving. Don't blame the kid.
2. If people are going to continue with these signs can they at least become mandatory for everyone else? For example I would love to see, "Illegals On Board." (No more hiding. At least with this sign I'll understand why you don't want to be pulled over for going over the speed limit.) "Phone on Board." Ah, so the swerving is not you but the phone being texted on. Got it. "Asian On Board." Do you know how many swear words this sign alone would save me? "Insecure About Manhood on Board." Ah, the big truck and speeding. Now it makes sense.
3. Now, now, now people I can sort of deal with the "Baby on Board" sign, but let's not get all crazy and graduate to the "Child on Board." Are you really going to keep updating your sign until it reads, "Lonely/Overprotective Mother on Board"? Again, there's no power or meaning to these signs. All they really mean is: You like to watch your toddler sleep...for hours. And sometimes you like to chew their food for them. You consider beating kids up who aren't nice to your kid at the park, and think any parent, who doesn't hold their child for at least 45 minutes everyday is being negligent. You are a crazy parent and that sign only confirms it. So listen, stop the crazy train and take down the sign. You will survive and your kid will become potty trained at a normal age. I promise.