Our landlord also loved using the really caustic industrial drain cleaner because he was too cheap to hire a proper plumber to snake out our back bathroom sink (it's part of the renovations I was talking about). I have a feeling the dozens of applications didn't do our clay sewer pipe any favours

Our next door neighbours failed a couple of years after ours. Apparently many of the houses on our street had theirs taken out the last time they paved and the owners who didn't were told it was a matter of time.

I imagine they were cheaper products used (at the time) due to the reconstruction in our city after the Halifax explosion (look it up if you haven't heard about it, a WWI munitions ship exploded and basically levelled half our city). I was impressed they had a 100 year lifespan, I didn't know they lasted longer!