Sometimes people want to do things themselves.
On a recent hardware store visit, I was dealing with [another] tricky plumbing problem. Old lead pipe welded to a brass fitting that needs to connect to my bathtub drain in a short space.
I described my situation to the sales person at the first store. They responded, "You can't do this yourself. Call a plumber". This is sound advice. However, it completely misses the point. I came to a DIY store specifically so that I could try this myself. Of course I would call a plumber if I couldn't figure it out in the end but this seemed like a reasonable problem to attempt.
The next store took a different approach. The sales woman listened to my problem, told me that "it might be tricky" but offered a few suggestions to try and some pieces that might fit my puzzle.
It worked...although it was tricky and it was time consuming.
In the IT business I see this all of the time. Customers want to do certain aspects of their IT services themselves. You can try to sell the benefits of using professional services but in the end it is their cost versus benefit analysis. Sometimes the best deal is to be there in a supporting role. "Try it yourself and if you get into trouble give us a call."
If our house only had a single bathroom I would have called in the professionals from the start because my tolerance for "outages" would be much smaller. The same goes in others fields. If customers can tolerate slower recovery, more effort or (possibly) less professional results, it might make sense to do it themselves. When they decide that they are done messing around with the problem themselves, and if we have been supportive along the way, maybe we will win that business.