Are Divisions in the Church Necessary?

The church is fractured. Over the past couple years, we have experienced a lot of division among Christians at the levels of networks and denominations, but also inside local churches and among friends, too. So is all this division a good thing? Is it only a bad thing? Will division work for the church's greater purity and final good? Or will division work to the church's final detriment and the lessening of her testimony in the world today?