When we did one of our surveys a couple of months ago - someone commented that they were reluctant to buy lampwork beads because of they weren't durable. We were completely surprised, but it's one of those things - sometimes you forget what other people don't know about a given topic.
Properly annealed lampwork beads are very, very durable. They will most certainly outlast us all. Archeologists have found lampwork beads that are now thousands of years old - durability is not a question. Glass is a substance that lasts and lasts!
What can happen though, is that glass needs to be cooled slowly to prevent it breaking, and this process is called annealing. Beads that are not annealed are subject to breaking, and the breakage is quite distinctive - they will crack neatly in half, or possibly into 3 or 4 pieces, two large pieces and 1 or 2 small, sharp, wedge shaped pieces.
(Technical stuff: Glass - like most other substances on the planet - gets larger when it is hot. Comparitively speaking, quite a bit larger than other items! Glass is a poor conductor of heat as well - and what happens is that the inside of the bead will still be very hot, and the outside will be cooling and shrinking. The inside is pushing out, and the outside is pushing in, and that creates a lot of stress in the bead. Annealing is the process of slow cooling that reliefs that stress. The larger the bead, the more essential this process is. )
It's hard to predict when an unannealed bead will crack - it can hang on for a year or more before finally cracking - which is deeply annoying if it is in the middle of a necklace!
There is an unwritten code about annealing - it is considered very inappropriate within the lampworking community to not anneal your beads.
So a properly made, annealed, lampwork bead is very strong. Round beads are hugely strong, and you can bounce them off concrete without any worries.
Beads with projections like wings or such - sculptural beads like winged angels, for instance - are subject to chipping if you drop them - wings might break off, etc. But these are from sharp, sudden blows, not normal wear and tear.
Raised dots on a bead could chip off if knocked about - look at the bead to make sure the dot does not have undercuts - that the dot comes up smoothly from the surface of the bead (like a mosquito bite) and looks to be integral to the bead. Bead makers are aware of this, and spend the extra time to ensure that the dot is properly melted in.
Feel free to ask the artist if the beads they make are annealed - many beadmakers who sell their beads online make a point of telling you this upfront.
In short - there are need be no concerns about the durability of lampwork beads - they will not fade, and if properly made, will not crack or break unless you truly abuse them. They will most certainly outlast you - so you might want to make sure you make provisions in your will for their disposition! I personally want to be buried with mine. Let some questioning archeologist find me in a thousand years - with all my beads - they'll probably think I was a queen.
Or a nutcase. ;-)