Mean time between failure: you can think of this as the average lifetime of the product, as determined by our members. Whenever a member "Retires" an object because they wore it out, broke it or consumed it, we use that to calculate the MTBF.
Climbing ropes: 5-7 years, or after a number of big falls. Of if you see a wear spot. Most climbing gear manufacturers will have a recommendation on when to retire.
this isn't 'reviews' – this is notes from actual users. list of all notes, list of photos of actual used gear, warranty info, etc.
Is it patagonia? They'll give you a nice gift card for returning old gear. Is it acrterx? They'll buy it back from you! You can also try http://giftyourgear.com/ or https://www.gearforward.org/ or even your local goodwill. You could sell it on the MP formus
That's a big question! Start with REI's Climbing Basics article, and then join a gym and just start!