When access decides the joint. Densely populated boards, pads shadowed by taller neighbouring components, very small terminals and fine rework are all cases where a broader tip physically cannot reach or would touch adjacent parts. If a chisel of appropriate width fits, it will almost always solder the joint faster and at a lower temperature.

Because heat crosses the interface through the area genuinely in contact, and a point provides very little of it. The molten solder fillet helps by bridging some of the gap, but the tip still gives up its stored heat slowly and takes longer to recover between joints. It is a geometric limit, not a quality or material issue.

It is the usual reaction and the wrong one. Higher temperature does not increase contact area; it oxidises the tip's iron plating faster, burns off flux before it can clean the joint, and raises the risk of lifted pads and damaged components. Fitting a tip with more contact area, or one with a small flat at the point, addresses the actual cause.

Degree rather than kind. Needle and micro-point tips are conical geometries taken to their finest, for fine-pitch rework and work under magnification, and they exaggerate both traits - the best possible access and the least heat delivery. They suit small, low-mass joints and cope badly with ground planes or anything with thermal mass behind it.

Often, yes, because the working point is small and carries the plating's thinnest, most exposed section. Any mechanical use - prying, scraping, pushing a lead straight - concentrates on that point and breaks through the iron plating to the copper beneath, after which the tip dissolves in solder and stops wetting. Keeping it tinned and never filing it is what extends life.