Should I always have the power cord plugged in to my Macbook Pro?

That computer is a battery-CAPABLE device. It is not optimized as a battery-operated device. (It is NOT an iPhone.)

Your computer performs best when connected to AC power. It can use the full output of the Power Adapter AND when doing especially challenging work will also freely "borrow" power from the battery. In some cases, even with the power adapter connected, the charged state may even decline during stressful work.

When used only on battery, your computer has no extra cushion of power, and may perform more slowly. However, for ordinary non-stressful tasks this may not be objectionable (possibly not even noticeable.)

In general, you should ALWAYS connect AC power when it is possible to do so, and only run on batteries (which could be somewhat slower) when no AC sources are at hand. Your Mac will NEVER over-charge.

You can leave your Mac plugged in as long as you wish. I seldom take mine off of power, even when mobile. Your device manages the battery and when plugged in essentially bypasses the battery or provides a trickle charge to it. There is no harm in leaving it plugged in

StockstillTiffany wrote:

I have a macbook pro and I do not charge but maybe every two days with no issues on battery life, so NO, you do not need to keep the macbook pro plugged into power. The purpose of laptops, macbooks etc are to provide users mobile (meaning movable) access to their devices instead of stationary devices like desktops. Macbook pros do not "always need to be plugged into the battery". Lithium batteries being over charged to devices can cause cell damage however as you mentioned Apple has battery technology that prevents this. So to answer the users questions specifically- No, you do not need to always have your macbook pro on a battery charge".

That is not the statement I was disagreeing with. I specifically quoted this from your first post:

"Leaving your MacBook on charge constantly will cause the battery to need a maintained charge at all times meaning your device will not function properly unless it's on charge."

That statement is incorrect.

No, of course you don't need to keep your MacBook plugged in all the time. However, it will not hurt anything if you do.

I have a macbook pro and I do not charge but maybe every two days with no issues on battery life, so NO, you do not need to keep the macbook pro plugged into power. The purpose of laptops, macbooks etc are to provide users mobile (meaning movable) access to their devices instead of stationary devices like desktops. Macbook pros do not "always need to be plugged into the battery". Lithium batteries being over charged to devices can cause cell damage however as you mentioned Apple has battery technology that prevents this. So to answer the users questions specifically- No, you do not need to always have your macbook pro on a battery charge".

Lithium batteries can be damaged by overcharging. Apple installed a battery monitor :

Optimized Battery Charging: This feature helps to reduce the wear on your battery and improve its lifespan by learning your daily charging routine. It delays charging the battery past 80% when it predicts that you’ll be plugged in for an extended period of time, and aims to charge the battery before you unplug. In System Settings, click Battery in the sidebar, click by Battery Health, then turn on Optimized Battery Charging.

A battery’s lifespan is related to its chemical age, which is more than just the length of time since the battery was assembled. A battery's chemical age results from a complex combination of several factors, including temperature history and charging pattern. All rechargeable batteries are consumable components that become less effective as they chemically age ~Per Apple

Define Battery Charge Cycle:

The more charge cycles your battery completes, the more it will degrade.

Thankfully Apple has implemented the battery optimizer on macbooks for users.

No, you do not need to always charge your macbook.

Your MacBook Pro  uses ‘smart charging’ to charge in the optimum way, and ONLY when necessary. Plugged in is Not necessarily actively charging. There is substantial hardware and software cooperating on battery and charging issues.

The computer is in control of the entire process. Your Mac will NEVER over-charge.

StockstillTiffany wrote:

Leaving your MacBook on charge constantly will cause the battery to need a maintained charge at all times meaning your device will not function properly unless it's on charge.

This is incorrect. Leaving the computer on charge preserves the battery (as charge cycles are not being used).

This is a topic than can be presented both ways. Over charging lithium batteries can cause cell damage. The user asked if "they needed to keep power constantly", No they don't. Apple does provide details on their technology here Charge the MacBook Pro battery - Apple Support

which may be beneficial to this user.

No, you do not need to charge your Macbook constantly. Leaving your MacBook on charge constantly will cause the battery to need a maintained charge at all times meaning your device will not function properly unless it's on charge. Your Macbook should not need a constant charge. If it does, contact Apple support. I believe the threshold of charging for Macbooks is around 40%, so only charge if necessary at that battery level. If you find the device is going through battery energy very quickly, contact Apple for support.

StockstillTiffany wrote:

No, you do not need to always charge your macbook.

Which is the exact opposite of what you said initially. Glad you've finally come round.