Some people come into dashcams, and maybe having used higher end action cameras for recording whatever, and so can get mighty let down by what dashcams do.
Some come in and say "must be able to capture plates" and you can also do that almost 100% certain if it is a mid summer day and the sun are out and you are driving across open prairie.
Otherwise the is a range of environmental factors that play in along with what the hardware used in cameras are actually able to do, so you end up with over a year, well a great deal of the time you will only have a tiny chance of a plate capture.
Add to that the American strange system of only having 1 plate on a car, and as small as possible and with all manner of background graphics on it, all doing nothing good for plate capture.
Thats why i always recommend dual systems for Americans, cuz even if your front camera have nothing to see on the oncoming car, your rear camera will have a chance if he have a plate in the back.
Over here in EU ville cars have big plates front and rear, so our chance of a plate capture are 2 X of a American.
If you like me think " i want a camera that document what i do with my vehicle" then you will have no problem finding a camera system as most will do that day or night, and only severe fog would put a damper on that.
Then beside that your camera can also capture a lot of other things, and maybe the day when you need it the most it will too.
But that guy liking pictures of cupcakes while he rear end you, he will not get away with claiming that you was driving erratic and changing lanes all over the place, cuz your camera have you driving in your lane and then ,,,,,BAM !
If you have a rear camera, you might even be lucky and have footage of him with his phone touching his nose, though it is somewhat of a call to expect, but best lighting conditions and you probably could.
The main thing is that you do not get to pay, and most cameras should be able to prove that, so stay within the law and you should be good with a camera.
4K cameras are cool now for daytime footage, they suffer a little in low light, though still fully able to log anything you do in relation to lane markings - side of the road - color of intersections ASO.
Some 1080p cameras often bases on the Sony IMX 291 sensor are more light sensitive, and so their footage at night are more relaxing to watch, but the degree of better low light abilities do not translate to better capture of little details like a license plate.
You can get plates alright at night even in the light of your own headlight, but the total difference in speed in between your camera bike and what ever cant be more than walking pace.
This is due to the fact that in order to capture enough light to make bright footage, the camera will maximize the exposure time for each video frame, but a slow exposure time + a target that move are a bad solution.
The crystal crisp pictures you see on race cars zipping by at insane speeds, well the photographer probably used a exposure time of 1000 of a second or 10.000 of a second, so even at insane speeds when he take the picture the race car only move a fraction of a inch in the time the picture are taken.
But a dashcam at night go as low as 1:30 second which are just slow enough to still be able to take 30 frames every second, but so slow exposures things dont have to be that fast before they move several inches while the photo is taken, resulting in what is called motion blur.
A photographer rule of thumb is, if you want to photo something at speed, you must at least use a exposure time of 1:500 second.
So the faster things you want to photograph or film the more light you must have to do so or the photo / video will be dark / under exposed.
This is also why you some times see super slow motion recordings are a little dark, even if it is filmed in the middle of the day with 100 % sun out, but even the sun and all its light are not enough if you want to take 100.000 photos in a second, or as some do millions of photos in a second.
Really fast and you need huge flashes that go off at the millisecond you want to record those valuable photos
At Holloman AFB they move things so fast, first of all they have to do it inside a plastic tube with gas in it as doing so thru air mean their experiment will melt.