> Lorenzini stated: "It had been badly welded together about a third of the way down and couldn't stand the strain of the race. We discovered scratches on the crack in the steering rod. It seemed like the job had been done in a hurry but I can't say how long before the race. Someone had tried to smooth over the joint following the welding. I have never seen anything like it. I believe the rod was faulty and probably cracked even during the warm-up. Moments before the crash only a tiny piece was left connected and therefore the car didn't respond in the bend."

https://en.wikipedia.org/wiki/Death_of_Ayrton_Senna

And the forces on a formula 1 steering column are also higher than on a road car, I imagine.

A proper weld should be very strong, I don’t think welding a steering column in itself is bad.