1. The cleaners were not professionals. It felt like they were just recruiting anyone who wanted a job. You could really feel this with the lack of passion from the cleaners and the severe lack of quality cleaning. Most of the people complained and were quite rude sometimes. Cleaning is very much a skill as much as it is manual labor.
2. People don't want to let just anyone into their home to clean. Especially for those that have valuables, you want someone you trust who is going to hopefully be your maid for years to come. I wouldn't want someone new every time and for that reason, I used HomeJoy only at our office but even that wasn't enough due to poor quality.
Someone on this thread further explained this well, which is that HomeJoy is at a high level, a match making service. Once you find a match, why do you need HomeJoy? Connect directly with the maid and have them come on your own schedule for a fraction of the price.
I used to feel the same way about Uber. If I found a good driver back in the day I would get his phone # and take him exclusively to the airport. Uber solved this with UberX and by having a wealth of seemingly skilled drivers that made it a true on demand service. Having to book an appointment like HomeJoy seems like it is not a true OnDemand service, just a nicer UI than any other maid connecting service.
AirBnB I feel had a similar problem. For frequent business travelers, finding the right place at the right price is awesome and I would usually try to stay at the same place and connect with people directly. AirBnB solved this with overwhelming demand for the service (the place I like may not always be available) and with their insurance policy and scheduling tools for renters.
In any event, I don't feel like HomeJoy failing is indiciative of a bubble in the On Demand economy. There were inherent principles of this business that made it destined to fail that others in the space won't have a problem with.