Do good intentions excuse terrible execution?

I heard about this story of the painting restoration gone horribly wrong in Spain earlier this week. A well-meaning elderly woman took on the task of fixing up a weatherbeaten fresco at a nearby church. It turned out so badly, the police initially investigated it as an act of vandalism.

... she could not understand the uproar because she had worked in broad daylight and had tried to salvage the fresco with the approval of the local clergy. “The priest knew it,” she told Spanish television. “I’ve never tried to do anything hidden.”

I believe her. So why was this whole incident treated as vandalism in the first place? Didn't the police talk to the parish priest?

And then there's the bigger question:

What was this woman thinking?

What possessed her to take on this project when she clearly had no idea what she was doing?

Then again, what was the priest thinking? Why on earth did he let a well-meaning but totally unqualified person take on such an important task?

Finally, should she be held responsible for botching this restoration so utterly? I mean, I very much doubt she can pay for undoing her handiwork and then doing a real restoration, but would it be appropriate for the community to criticize her? Or is she clearly so divorced from reality that she simply should be kept the hell away from paint and brushes?