Practice holding Head Level while peeking angles. Click the target as soon as it appears behind the wall.
The walls will slide away. Hold your crosshair at the center line (Head Level) and hit the target.
Crosshair Placement is the skill of keeping your aim at head-level and focused on where an enemy is likely to appear. It is widely considered the single most important skill in tactical shooters like CS2 and Valorant.
If your crosshair is already on the enemy's head when they peek, your reaction time is effectively 0ms—you just have to click. If you are aiming at the floor, you have to react, move the mouse, and then click, which adds 200-300ms to your Time-To-Kill.
Good placement cuts the amount of correction you need after an enemy appears. In tactical shooters, that often matters more than raw flick speed because your crosshair is already close to the most likely head level or angle.
On most maps, boxes and crates are exactly "one head" tall. Use them as a reference. Also, look at your teammates' heads during the buy phase.
Yes. Good crosshair placement ("Lazy Aim") beats snappy flick aim 9 times out of 10 because it is more consistent and requires less effort.