Medical Technology continued development

While I sit here in the (sunny?) foothills of Southern California, listening to this strange rain-stuff pelting the windows and saturating the lawn, I am trying to determine how best to describe the current state of medical technology development, and its implications, for competitors in this industry. While there are momentary ripples of ups (a new drug eluting stent approval or an industry-shaking merger) or downs (reported deaths or other serious complications associated with a device), it is otherwise an extraordinarily stable marketplace. No wonder medical technology tends to runs slightly counter to the general economic trend, drawing investment in down economies (when there is nothing better to invest in) and being forsaken for dotcom-like boom stocks. People keep getting sick, needing healthcare and, in lieu of some miracle drug coming on the market (and sometimes being taken off the market a la Vioxx), creating demand for medical devices. There are just enough hurdles, and not enough chance at huge economic rewards (save the first year of a new device's release, like when Cypher came out) to draw hordes of entrepreneurs. It can be tough run the gauntlet of funding, development, and clinical trials (cycle these a few times) before gaining approval. But the growth keeps coming.

Outside, another sudden squall has started indiscriminately splattering the sidewalk, filling the gutters with another rush of water that is sure to be a nasty flashflood somewhere down the line.

What's behind it?