This is a good principle, but I think 6 months is a bit too much. It probably depends on the size of the purchase: new car? 6 months. TV? Maybe a couple weeks. Clothes? Give it a couple days.
6 months is good for a TV though, because then new tech will be out. Then you will wait 6 more months to be sure you want that one, then new tech will be out. Then you will wait 6 more months to be sure you want that one.
Sort of off-topic: I'm thankful to the TV industry for getting me out of this trap. In 2014, I moved, and bought a larger TV to fit in my larger living room. Not even a year later, I sold it and went back to the previous model (that I thankfully didn't sell; I used it as a secondary PC screen). TV operating systems are total shit nowadays. (Or, at least the one that I got was.) My old TV may be smaller, but when I press the power button, it's fully operational within a few seconds, not minutes. And it reacts to button presses in under a second, not over 10 seconds.
Yes, I hate the fact that when I turn on my TV, it takes a full 5-6 seconds for it to respond to the remote. This can be very bad if the volume was up high, and you turn on the TV late at night and are greeted with blaring sound an no-way to turn it down until you have already woken half the house.
When I bought my car I noticed a "Start Up Volume" feature. I could be blaring the stereo on my way home, turn off the truck, then come back out in the morning to go to work. I wouldn't be deafened by the sudden jump in volume. It always starts at an adjustable level for that input source.
I don't understand why everything else that has a speaker doesn't have this feature.
The most outrageous thing was the "Sources" menu (where you switch from HDMI input to TV), which took 1-2 minutes to load (whole going through several different "Loading..." screens). So I always had to remember to put the TV back into TV mode in the evening (after using it as a PC screen to watch internet videos).
Or needing to keep that one TV remote around because the Source or Exit button on the universal remote won't let you exit the "Sources" screen. But it'll control every single other function. Hate that!
