Cloud systems require internet access and a lot of it, as much as 4 Mbps per camera.  So if you have internet bandwidth constraints or data caps then the cloud is not for you.

Cloud Bandwidth Calculator 

6 Cameras @ 1080p (High Setting) x 4,000 Kbps (4.0 Mbps) = 24 Mbps upload bandwidth.

On average, depending on plans (motion only or continuous) each camera will use 380 GB per month. That is over 2 TB of bandwidth each month!

Source

Also for the real security nuts out there. In the event of an internet outage or ninja’s coming to your house and cutting your internet line, a cloud solution is not going to meet your needs. Not to mention the numerous ways WIFI signals can be disrupted which will render your cloud cameras useless.

This is where cloud systems really shine. Most cloud cameras can be set up in minutes and quite easily. Most cloud cameras have you install a mobile app and scan a barcode and you are instantly recording your video feed.

NVR’s can too be simple to set up but they do typically require more planning, wiring, and some technical knowledge to get them configured.

As cloud systems are “in the cloud” remote access is a basic built-in feature as all access is “remote”. 

NVRs will require additional steps to setup remote access. Either firewall rules, a VPN to your home, or for those that like to run around outside naked, enabling Universal Plug and Play (UPnP).

Quick tip: If anything is as simple as one click to allow remote access into your home network…bypassing your firewall…it’s too good to be secure.

Cloud systems typically subscription-based and require a monthly or yearly fee. This fee is usually based on the number of cameras, if you want to record continuously or only motion events, and how long you want to retain the video recordings for.

An NVR will not typically have a subscription aside from software such as BlueIris that you have to pay a software fee in order to maintain security updates. 

I say typically as there are a few systems that are not so typical:

• Google Nest, while having a monthly subscription, now has a flat fee for all your cameras and Nest devices in your home. 
• Wyze Cam will record up to 14 days for free to AWS with no subscription or monthly fees required.
• The overall cost of an NVR needs to be considered with determining ROI in comparison to a cloud-based system.

Cloud-based systems, for the most part, cannot be customized. To include:

• Where and how the video is stored.
• Backup options in the event data is deleted.
• Installing plugins to give you additional customizations. 
• Using scripts to automate basic tasks and deploy new systems.

The majority of maintenance for cloud-based systems is managed by the cloud provider while on an NVR system you will be responsible for software, security, and firmware updates. 

Cloud-based systems are great at doing the basics such as recording events, reviewing motion events, and saving clips. Anything else you would ever want to do is either not an option or requires funky workarounds. 

Only a few quick options available on an NVR and not a cloud-based system:

• Custom recording schedules based on motion events. For example, recording at 1080p continuously and 4k when a motion is detected. 
• Trigger IoT devices. For example, when motion is detected after sundown in the driveway, turn on the driveway floodlight. 
• License Plate Reader (LPR) camera support.
• Support for more cameras without getting locked into a brand by using Open Network Video Interface Forum (ONVIF).
• Footage storage options and backups.
• More control of settings such as frames per second (FPS) aka frame rate which can have a significant impact on video quality and video storage.