Kind of interesting mechanic difference if you read through those Bulbapedia articles. From what I gather, reading both articles, the number of turns disabling lasts is sort of based on a hidden counter that drops at the end of each turn including the turn you actually use the move (sort of like Perish Song)
The move Disable always gives the counter a value of 4 while Cursed Body always gives a counter of 3.
However since Cursed Body activates in response to getting hit with a move already used that turn this means it always disables the move AFTER it is used. So the counter falls from 3 to 2 before the opponent is even given the option to select moves again. So cursed Body force you to go without a move for 2 turns.
On the other hand, Disable is a move based on the user's speed so it can activate before the enemy attacks and thus potentially stop the use of their move if they are using the same move as last turn. From there it is always 3 turns the disable Pokemon can not select the disabled move.
In the end it's generally the critical move you need to be using that gets disabled and so you are forced to switch. But if for some reason you think you'll accomplish more or risk less by staying in you can always know how long you're going to go without the disabled move based on how it was disabled.
The move Disable always gives the counter a value of 4 while Cursed Body always gives a counter of 3.
However since Cursed Body activates in response to getting hit with a move already used that turn this means it always disables the move AFTER it is used. So the counter falls from 3 to 2 before the opponent is even given the option to select moves again. So cursed Body force you to go without a move for 2 turns.
On the other hand, Disable is a move based on the user's speed so it can activate before the enemy attacks and thus potentially stop the use of their move if they are using the same move as last turn. From there it is always 3 turns the disable Pokemon can not select the disabled move.
In the end it's generally the critical move you need to be using that gets disabled and so you are forced to switch. But if for some reason you think you'll accomplish more or risk less by staying in you can always know how long you're going to go without the disabled move based on how it was disabled.
