The New Zealander appointed to head a United Kingdom inquiry into child sexual abuse resigned "because she found it too much for her", Home Secretary Amber Rudd has suggested.
Dame Lowell Goddard, a High Court judge, resigned from the independent probe last month, 18 months into the role.
Earlier this week it emerged that following her departure she had called for a complete review of the inquiry.
Ms Rudd was questioned about the episode as she appeared at a Commons committee on Wednesday, local time.
"I think she went... because she found it too much for her and although she could contribute to it and there was some good work done in the past year, ultimately she found it too lonely. She was a long way from home and she decided to step down.
"That's all the information I have about why she decided to go."
Ms Rudd said she had never met Dame Lowell but she believed she cared about the inquiry.
"But she did set out in the letter that she didn't feel that she could actually deliver on it."
In her written evidence to the committee, Dame Lowell said: "With the benefit of hindsight - or more realistically - the benefit of experience, it is clear there is an inherent problem in the sheer scale and size of the inquiry (which its budget does not match) and therefore in its manageability."
Dame Lowell said she was pleased to set the inquiry on its way, adding: "Ultimately however I had to face a situation which I could not solve and which would continue unless challenged. I resigned to make that challenge occur."
Ms Rudd denied the inquiry was underfunded.
Last month Professor Alexis Jay was named as the inquiry's fourth chairwoman.