Most automotive batteries are rechargeable lead-acid batteries that are primarily designed to crank an engine with an electric starter (SLI Battery). Because of that, they are designed to give one quick burst of current rather than a slow discharge. Repeated slow/deep-discharging will reduce the capacity and lifespan of an SLI battery. Types of slow discharge include listening to music while the car is parked, leaving headlights on for an extended period of time while the car is parked, and a dash cam recording while the engine is off.
Because SLI batteries aren't designed for deep-discharging, traditional hardwiring kits like the Power Magic Pro or Thinkware hardwire kit are not ideal for the car's battery in the long-term. Traditional hardwiring kits which work by monitoring the car's battery level and cutting off power to the camera at a user defined voltage (typically between 11.8V-12.2V). On most passenger vehicle applications, a dash cam can run a fully charged 12.6V battery down to 12.0V in 12 hours or less, that means this is happening on a daily basis if you have a hardwired dash cam.
In addition to the battery drain caused by the dash cam, even after the cut-off voltage is hit and the dash cam turns off there are other electronic systems in the vehicle such as a proximity key sensor or alarm/security system that will continue to drain the battery. For that reason, even if the hardwiring kit is working properly and cutting off the dash cam at the desired volQage, there is still a risk of returning to a vehicle with a dead battery that will not start. Because of this, we don't recommend using a traditional hardwiring kit on a vehicle that gets parked for several days at a time unless that vehicle is plugged into some sort of battery maintainer.
The extent to which a traditional hardwiring kit may be detrimental to you depends on how frequently you drive, the specs of your car's battery, and how much parasitic drain your vehicle suffers from. In all situations though, the most recommended dash cam power solution is a dash cam battery pack such as the Cellink Battery B. This option gives you the peace of mind that it won't wear down your battery and you don't have to worry about whether you can start your car. You also don't have to worry about having to replace your battery sooner than you would need to otherwise, replacement car batteries can cost upwards of $200 depending on the vehicle.