Rapidly touches every piece of wood in sight.
34 years of driving, I have never had a breakdown that required outside assistance to get me home.
The closest problem to needing a tow home, that I have had, was a broken clutch cable on a Renault 19 16v. Although even that can not be classed as a full breakdown by your rules as I did manage to drive it 124 miles back home with no clutch as the cost of recovery was ridiculous.
Did have one occasion of a brake pipe splitting, (old mk2 Escort) but managed to drive the 3 miles or so back home on the hand brake, so again not much of a problem.
Other than that have had approx 12 punctures necessitating replacement of tyre & wheel at side of road.