Why do I suck at Call of Duty Black ops

"-You think you're Super Mega Sniper Elite 007"
>>>They said it themselves...In games like this,the human brain is trained to spot anything that's moving,so their suggestion to sprint and stop,completely fails.It's far (FAR) easier to spot someone sprinting than someone crouch-walking!!!

"-You never stop reloading"
>>>Please read what GR says in their article and then just think of this: It's called sprinting!!THAT'S your protection if anyone shows up when you're reloading!Just sprint to the nearest wall/corner/obstacle for cover while reloading...You can earn THREE things by doing this...
1) Fully loaded weapon
2)replenishing your health
3)you have the element of surprise against your opponent who NEVER knows when you will show yourself again!!!

"-You don't use what you brought"
>>>Switching weapons is more ineffective than just reloading because you also have to remember to switch tactics(few people can do that all the time).In addition,I use my main gun and grenades(in GoldenEye though) only and I can keep going for 3-4mins...Another thing is that as long as you are trying to decide where to place your proxy mines,you are defenseless...

"-You're impatient"
>>>Learn the map structure...It's easy and effective...Learn your paths from place to place and always have some emergency spots to get cover if anything goes wrong...If you can do that(it's very easy),then sprinting like a maniac is not bad at all,it's even good!
BONUS TIP:
"[...]the simple lag time in getting your gunsights up after running is more than enough time to leave you waiting to respawn[...]"
>>>In a case like this,you can crouch and have all the time you need to kill most(but not all) of the enemies coming in front of you and usually have set the turning and cursor(ADS) speed to low levels...

"-Your life means too much"
>>>You know,GamesRadar,this will NEVER change unless the Perks System gets dropped...These players are protecting themselves to do big combos and earn XP that the developers made necessary for upgrading and unlocking sweet modes in multiplayer...PLUS,they are helping their teammates by providing a safe spot for them to return(for health replenishing and/or ammo refills) and they save others from enemies coming from behind.
This is the developers' fault!IMO,they should all drop the Sniper Rifles and never use them again!

"-Your life means too little"
>>>GR says that it's bad that players respawn next to you and immediately rush to the battles and then get killed...I'm saying: Why is that bad?What else do they have to do?Stay put and cook some dinner?
GR says that it's better to stick with teammates...They forget that doing so attracts too much attention and if an enemy comes from behind or drops from a higher ground level,they(enemies) get an easy kill-streak.GR also tells players to move more slowly...Again,this depends only on if players know the map.

"-You use assault rifles for everything"

If any of these are oh too familiar. That is the reason. If none of them are, then you must be a complete failure and there is no possible way of winning for you. BREAM!!!