Scoreboard Arguments behaving weirdly.

The Score arguments (i.e. "@a[score_name=x,score_name_min=x]") aren't behaving as they should in a somewhat indescribable way. I will do my best.

What I expected to happen was...:
The following command in a command block running in a loop: "/scoreboard players add @a[score_Pulse=2] Pulse 1" was expected to add one to the dummy score of the "Pulse".

What actually happened was...:
The above command added to the score indefinitely. Strangely "/scoreboard players add @a[score_Pulse_min=2] Pulse 1" does stop the count at 2. But using just score_Pulse=2 doesn't prevent the score from counting if it's below 2.

Steps to Reproduce:
1. Go into a creative, cheats enabled world
2. run this command "/scoreboard objectives add Pulse dummy
3. make a redstone clock.
4. connect a command block to the count that has the following command: "/scoreboard players add @a[score_Pulse=2] Pulse 1"