Particularly given the launch record of the Ariane 5 platform. I did some quick research, and no modern launch platform has as high a mission failure rate (4.5%.) The Delta family comes close at 4.4%, but that's a 50yr launch history. The Delta 4 iteration has had no failures.
As I wrote elsewhere, the bulk of those failures were in the first 15 launches, after that it was a very long string of one success after another with one partial failure in 2018.