Quick installation means cheaper build cost, means cheaper price, means more sales. The manufacturers don't necessarily share your passion for long lived equipment. Turnover means profit.

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Re road triple or compact, there is a cheaper way. I do this because I go on one or two euro-mountain-pass cycling weekends per year - but spend most of the time in flatter regions near home.

Get a mountain bike cassette (I use a 32t lower), a longer chain to go with it and long cage derailleur. I keep the 3 of them together - switching the set over for climbing holidays. It's not as low geared perhaps but it sees me up big hills often with a gear or two to spare.