Why don't dashcam's have built-in memory?

[Sunny]

There may be some expensive ones with built-in memory but why don't most of them have any memory?
Even 1gb will be great for recording.

Why this question?
I was reviewing footage from my cam and the card was in my PC slot.
Next morning I drove off without knowing there is no card in the camera.
Thankfully, nothing happened but if something had happened, there would be no footage.
If the camera has even small memory, it'd be enough to record few minutes video (with no protected file feature so it always overwrites).
Adding 1gb doesn't even add few bucks nowadays.
What say you?

 

[Mandami]

I don't think it will resist for too long time if you'll rewrite it over and over.

 

[Sunny]

I don't think it will resist for too long time if you'll rewrite it over and over.

I meant it's only when the microsd card slot is empty, not for everyday use.
In case you forget the card or to test when you first receive it.

The rewrite over and over is to have the space available for new video instead of filling the memory with protected files.

 

[USDashCamera]

another reason why i like my blackvues. they give an audio warning tell me to put the SD card in... but its usually in anyways since I just use the wifi to transfer files over to my phone.

 

[mollydog]

another reason why i like my blackvues. they give an audio warning tell me to put the SD card in... but its usually in anyways since I just use the wifi to transfer files over to my phone.

That I did like about my Blackvue, it did give you warnings of what was happening, starting,stopping or a problem with the card or itself. it will ad a few $$ to the cost to ad this in other DVR’s but I think it’s a feature thats not a gimmick like the bling they like fitting round these cameras

 

[Bungus]

Mobius's blinking red light does that too.

 

[abarth]

I know my mini has 8GBs built in. it's a good feature for that exact situation you described.