Soldered Joints, Crimped Joints

Crimp using decent connectors, make it TIGHT, solder it, use a decent heat shrink. If I think it could still be threatened by Iowa's environment, I then cover it with liquid tape (but only if unseen such as under the car)
I have wired campers, trucks, tractors, and my own cars - and so far haven't lost a joint but then i'm only 61 so I suppose I can't say "they will last 100 years" because I've not run that test YET.

But i've still got some of my electronic projects and such from my early teens - things I soldered with proper rosin core solder - not a bit of corrosion or appearance of acid, and so on.

I used to work for Compressor Controls Corp, a world-wide EE company and maker of very high-end turbo-compressor control systems and controllers for the electric grid. 
They crimped, soldered, and used heat shrink. In fact when they were doing some massive changes about the time I left the company their head of the manufacturing department was doing some housecleaning and giving away big rolls of heat shrink they no longer used. Much of it was either way too big or too small for automotive but I still have some sizes of it on the rolls hanging in my garage. 

They did tend to wash things - sometimes LITERALLY in a dish washer - yeah, entire circuit boards went in there and yes it was a standard dish washer like from Sears. 

I did laptop computer board-level repairs and never had an engineer yell at me - their computers took more abuse than anything I'd ever seen, coming back covered with coal dust, acidic whatever from the environment they were in (petrol rigs, pumping stations, refineries, etc.) 

I did much of the wiring on my little Eagle a number of years ago - and on my 70 Javelin a dozen years ago -everything is still fine.
Perfect? Naw, some of you here would likely find flaws, but reliable, and so far, have stood the test of time. 
I agree expensive crimp tools and the terminals made for them are ideal - but unless you have those and expose NO copper, well........... 
I've also opened up factory wiring and found GREEN up inside the insulation several inches - so apparently even the perfect crimps aren't perfect as moisture can wick up any exposed copper stranded wiring. 

Yeah, some of these I had to cut off a couple of inches back due to corrosion up inside the insulation.