The chief executive said that the company had made progress in improving the health of conversation on Twitter, but admitted that it had placed most of the burden on the victims of abuse.
Speaking in an interview carried out entirely on Twitter with technology news site Recode’s Kara Swisher, Mr Dorsey said: “We’ve made progress, but it has been scattered and not felt enough.
“Changing the experience hasn’t been meaningful enough. And we’ve put most of the burden on the victims of abuse (that’s a huge fail).
“It’s recognising that we have to be proactive in enforcement and promotion of healthy conversation. This is our first priority in health. We have to change a lot of the fundamentals of product to fix.”
The Twitter founder said that the social network was exploring ways to proactively enforce and promote health on the platform and was putting physical safety as their top priority.
“We have to consider first and foremost what online activity does to impact physical safety, as a way to prioritise our efforts,” he continued.
“I don’t think companies like ours have admitted or focused on that enough.”
When presented with a tweet from a Twitter user who informed followers they were moving to Instagram until Twitter fixes its harassment issues, Mr Dorsey said it “depresses” him.
“Feels terrible,” he commented. “I want people to walk away from Twitter feeling like they learned something and feeling empowered to some degree.
“It depresses me when that’s not the general vibe, and inspires me to figure it out. That’s my desire.
“We made something with one intent. The world showed us how it wanted to use it. A lot has been great. A lot has been unexpected. A lot has been negative. We weren’t fast enough to observe, learn, and improve.”
Twitter’s recent quarterly results for the final three months of 2018 revealed that the number of people using the site each day was up 9% on this time last year to 126 million, and up two million on the previous quarter.
But the number of people using the site on a monthly basis fell from 326 million in the previous quarter to 321 million in the last three months.