The class is highly accessible. It's the only series in the world to have open regs for the top class...
Hybrids are a thing because it helps understand electrical power and potential alternatives for road cars, then what currently exist. Le Mans and by extension the WEC isn't here for just the fans in reality it's here for the Manufactures to run glorified R&D and get PR marketing and a shiny trophy as well. With the LMP1-L getting a large reboot you will see the non-hybrids race again.
Though I will say there have been plenty of years where non-hybrid units failed just as badly and often. Picking a random time you remember doesn't reflect the true state of hybrid vs non-hybrid. If we are to actually advance motor racing these things should be attempted or we'll get cars that don't ever progress and run the risk of killing off many series because there isn't a point if there isn't a return for the manufactures investing.
EDIT:
Also the year you mention had 3 cars from the top contender see engine failures, while the Audi as usual played the long game and lived to win it.
Only five LMP1 cars finished out of seventeen. It's also currently a more dominated manufacture series, than it was in 2010.
None of these cars (other than GTE it seems) are easily serviceable. Toyota always seems to have a critical failure that is beyond something that can be fixed and sent back out to challenge for a win later in the race or podium. Wiring loom failure, overall ICE failures, Most of the issues I recall from Audi were usually turbo related (or just being slow and steady) and so it didn't take much to fix. Porsche is similar, they're pretty solid for a car that has an engine as a stressed member running a 24 hour race. This hybrid unit failure was quite rare and obviously attributed to the heat.
Last edited: Jun 19, 2017