Even with their presence in Syria, the violence continues. If Assad isn't going to change his murderous ways with international monitors, it makes no sense to leave them around to congratulate the government for behaving. Al Jazeera:
An advisory body to the Arab League has called for the immediate withdrawal of the group's observer mission in Syria, saying its monitors are inadvertently helping the government cover up continued violence. The Arab Parliament, an 88-member advisory committee of delegates from each of the League's member states, said on Sunday that the violence in Syria was continuing to claim victims despite the presence of observers. The monitors are on a month-long mission to ensure the government of President Bashar al-Assad complies with the terms of the League's plan to end the crackdown on dissent.