Hi Andrei, If something 'leaves a lot to be desired', it is unsatisfactory. The 'current state of machine/computer translation software' is unsatisfactory-- it does not work well-- we desire it to do much more or much better. Therefore, your second example doesn't really work: 'We are still discussing the matter of candidacy and it leaves a lot to be desired'-- if you have simply not yet decided on a candidate, the discussion itself is not unsatisfactory, it is continuing.
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