There isn't a "better" one, it's which one you prefer.
Wireless mice have the advantage of less resistance to your movement as the cord on wired mice drags along the table and/or other objects. If you have a particularly messy desk then it may be difficult to accurately move the mouse if you are constantly putting objects on top of or near the wire. A mouse bungee can help nullify a lot of the disadvantages of having a cord. One description of a mouse bungee starts with:
"You'll feel as if you're using a wireless mouse"
A wireless mouse however has the disadvantages of needing to be charged regularly. This can be quite bad if you play for long periods of time or forget to charge it sometimes as the mouse may just stop working in the middle of a ranked CSGO game, which may be the difference between winning or losing.
Also the battery can only be charged so much. You'll need to buy new batteries every now and then (they can last a few months to a few years). The other disadvantage of using a wireless mouse is that they are generally much heavier than wired mice, which is again dependent on personal taste but many people will have preferences for the weight of their mouse (most mice have interchangable weights) which is generally less than a lot of wireless mice.