First let's look at the situation that spurred Germany into such advancements: WWII. To say that they had the best equipment is misleading given that the competition was pretty strong.

Anyhow. I'll focus on German aviation and the Jet technology because that's generally my area of knowledge.

The Me-262. Yes it was indeed a jet fighter that was introduced circa 1944. But was it the best? Not really, the ME-262 suffered from extremely large amounts of unreliability and worse still, bad training. It's worse enemies was the incredible fragility of the Junkers Jumo 004, an engine that coupled with low quality fuel only had the average lifespan of ~20 hours before overhaul. Incredibly low.

Why? Well first of all, most of the technology was very rushed, although they pushed hard for it, what I've noticed was that unless change was warranted, designs usually stayed for a good amount, I.e the Supermarine Spitfire or the Me-109. The Me-262 while not utterly ineffective and very good on paper, suffered from logistics issues and manufacturing issues. Couple with the sheer number of P-51s it had to face and no ratio would've helped it.

Anyhow, the Germans really weren't that ahead of the curve. Despite claims of the ME-262 being created in 1941, it was still using Junkers Jumo 210 engines in it's prototype stage. Partially because the BMW 003s were far too heavy. It wasn't until 1944 where the jet was even used in war. Months later the Gloster Meteor would be introduced in limited amounts in July of 1944 and the United States was well onto developing the P-80/F-80 Shooting Star as well as developing and cancelling the P-59 Airacomet.

And then we have the De Havliand Vampire as well, which was intro'ed in 1945 but was well on it's way by 1944.

So to give credit to the Germans for rocketry and Jet technology would ignore the fact that simultaneously the US and the UK were well on their way with their own Jet fighters. Ones which incidentally didn't have the hazards of the Me-262 or the terrifying tendency to explode like the ME-163.

As to what transpired? I could only guess, but desperation and necessity to get the cutting edge led to Nazi Germany pumping out many many ideas, some innovative..some...Not so much.. But invariably, I would wager that a combination of wartime pressure and a large drive to create new weapons would drive most of these experimental weapons. Weapons which honestly were not nearly as effective as they should have been due to the circumstances.

As to their efficiency, personally I would avoid using that term. The V-2 cost Germany more laborers than it's estimated death toll. The Jets worked on a blue moon (although deadly when it did) that required a lot of favorable conditions. Most of the advantages were negated due to the logistical problem of fuel consumption and Allied strafing. That isn't to say that they were useless, but despite the technology they employed, it didn't really give Germany that much of an edge. And their innovations weren't in fact entirely new.

Sources:

Bekker, Cajun. The Luftwaffe War Diaries: The German Air Force in World War II. New York: Da Capo Press, 1994

Price, Alfred. The Last Year of the Luftwaffe: May 1944 to May 1945. London: Greenhill Books, 1993.

hi! there have been a few discussions about Germany's reputation in engineering - check these out for previous responses

• When did "German Engineering" become a thing and how did it come about?

• Why is German Engineering 'a thing?'

• How did Germany overtake Britain in industrial output by the early 20th century, despite the former's lead and straightforward advantages?

• What led to the German scientific powerhouse of the 20th Century?

incidentally, my search also turned up this post, which you may find interesting

• Was Germany more advanced technologically than the allies during WWII? How did they progress faster?