What happened, as often happens with those enthusiastic movements, those things get formalized and Quakerism becomes a religion of "don'ts" and "thou shalt nots".
When people ask "What do Quakers believe?" you run off this litany of things that we don’t do. "Well, we DON'T baptize, we DON'T do communion, we DON'T take oaths, we DON'T...” and as part of that Quietist Quaker culture, we don't do music, we don't dress the way the world does, we don't worship the way the world does, and that became hardened.
... and it had just hit hard after the Civil War, so you’re already spiritually exhausted from the migration, the battle of the Underground Railroad, the war, the poverty, and in come these holiness revivals. It was just singing and vocal prayer and praising the lord and people's eternal assurance that they had been saved and sanctified. They knew if they died tomorrow, this is where they’d spend eternity.
And you go back to these Meetings and the elders are saying, "Well... you can never be absolutely sure, you know... its too much creaturely activity. It’s too much self will. You have to be - if you think you’ve been saved - your personal salvation... you know, that’s pretty prideful.”
So in order to literally save the Quaker youth for the Friend's Church, the elders, who had no evangelical tendencies themselves, would incorporate some of these, what we call "new measures." Bring in some hymn singing, some vocal prayer, some planned messages out of the silence to add some more spiritual vitality to the meeting. And that evolved from the 1860’s and 70’s into kind of a full blown pastoral protestant form of worship.
It’s the old dilemma: in order to save the village, we had to destroy it... the old Vietnam adage. In order to save Quakerism, they had to essentially destroy the Quakerism they inherited.
But, in retrospect, we probably lost more than we gained. But they had to do it.