First of, let's begin with the advantages:
-They provide plenty of cover.
Like humans, they'll always provide cover if they can. With their aimbot, they can easily pick off the enemies without doing friendly fire, which brings up to the next point.

-They almost never do friendly fire
You have NO idea how important that is. How many times on expert did you see a person trying to cover you, only to get incapped by the player? A lot, right? That's not the case with bots. You can walk freely in front of them without worrying getting damaged. (WARNING: IF YOU HAVE 20 HP OR LOWER, WATCH OUT, THEY MIGHT INCAP YOU. I TRIED THIS ON EXPERT)

-They have aimbot.
With the aimbot, they can track down enemies such as smokers running away, chargers going after a player, or even help you while picking them up.

Now here comes the disadvantages you must expect when teaming up with a bot.

-They'll heal themselves or you when you're 40 or under.
You have NO idea how annoying that is. Many times I pop in some pills and with 45 temp hp left, the bot attempts to heal me! Note: you can stop them by pulling out a medical item. However, it'll stop them for a good 5-10 seconds, then after that, they'll go back to healing you.

-They'll pick you up no matter what.
I know what you're thinking. "But that's an advantage! Why is that a disadvantage?!" In expert, you have NO idea how terrible that is. A huuuuge horde comes out and when I get incapped, they try to save me, thus leading them to be incapped. It does not help unless its on easy/normal. Other than that, terrible and useless.

-They can't pick up grenades.
I know they cannot pick up grenades but you gotta admit, that's terrible. You need all grenades equipped by all teammates to complete the stage easily. Bots cannot do that, so completing the stage, if not the campaign is going to be difficult.

-They're unreliable aganist special infected.
As reported by many players and experienced by me, bots will stand in spitter goo, watch you get destroyed by chargers and get tangled by smokers. Yes, I said they will cover you when they have the chance but thats aganist commons. Special infected is when you gotta watch for yourself and not depend on a bot to help you out.

-They can't pick up defibs.
This is annoying on single player because if you die at lets say right near the saferoom, the WHOLE game starts over. It's annoying and frustrating!

I hope this helps to point out the advantages to the people who think bots are worthless and pointing out the disadvantages to the people who think they're just perfect. But in the end, this is a co-op game, bring some friends! I'll make some new guides soon. Share this with some friends, comment and have an excellent day.

I will be starting a series of guides with this.

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