In many instances, airplane lands, has to be cleaned, restocked and refueled if needed, for the next flight to be boarded.  If at prior city was foggy, snowing, etc, and flight was delayed, your flight will also be delayed.  Also watch the amounts of carry ons brought on board, and the difficulty of storing all of it into the over the seat racks. 

Early in the morning, one flight may be delayed 10 or 15 minutes.  Multiply that by many flights each day per planne, and you will see chaos in late afternoon flights without weather problems.  Add weather, and now you see why delays happen.

Actually delays in flights are a worldwide phenomena and are not confined to China alone.  Airlines in the United States have developed a now-notorious not-on-time record and it became so bad that the government had to step in.  The American newspapers were full of stories and complaints from furious flyers whose planes had been held for hours and hours on the tarmac, without air conditioning, without food and water, without anything.

There must have been a serious reason why your flight to Xiamen was 5 hours late.  Was it the weather?  Was their a cycloon in Xiamen?  Was it a mechnical problem?

Never had that problem before on China airlines. It could possibly have something to do with the weather conditions. If it is thundering outside, foggy or snowy the airline may have to take the delay. They don't want it to be dangerous to fly and you might have just got unlucky on the day you were expecting to travel. 

So yes, the weather would more than likely be the reason your plane was delayed. I'm just wondering why the airline didn't tell you the reason why they were delayed because most airline companies at least will tell you why there is such a delay. Next time ask the airline company because every flight that I know of if there is ever a delay they will explain the reasons why, and won't let you waiting for 5 hours without any answers or explanations.

Because this country and its culture are unorganized and ineffecient by nature. I once ate my in flight lunch on the Tarmac. 

5 hour delay from Changsha - 3 hours in the airport, 2 hours on the plane

i would understand the weather would play some part, especially during the rainy season, but there were no storms along the flight path.

reason given? extra security needed at Beijing due to Obama visit.
Beijing friends heard nothing about it while waiting !!

4.5 hours in HZ, to HK... lucky it was all booked through the one website, so when I finally got to HK, no issues in changing my connections (to the next day, cos I missed 2 international flights), and putting me into a nice hotel...

I frequently use China domestic flights and by far and away the biggest reason for delayed flights is related to air traffic control. There are simply too many carriers using China air space.

It is not meant to be easy to travel in China, possible but not easy. 

Because children's poo is being cleaned off the aisles and flight attendants are recovering from punch-ups with male Chinese passengers.

its china. my red eye flight to thailand was delayed, then canceled, then delayed again. i could have gone home and waited for my afternoon flight, which it finally end up being.

Because it takes too many hours to clean the toilets after a flight and it should be clean for take off.

LZ is hot! 

Maybe because they take off late. This is common in the US too. Mostly because bad weather ( snow) at each destination the plane goes that day. one hour at their first stop one hour at their second stop etc etc.

So often? It's only often that they become delayed because of a bad thunderstorm or due to any other weather related issues. Blizzards, snow storms, thunderstorms, hurricanes can all cause the delay. I've never been stranded at an airport here before. 

Ha ha, I said: "delay"!

While weather sometimes plays a part, mostly it is China's inability to plan or follow a routine.

I took 8 flights in China last summer and 6 were delayed from 2 to 5 hours and not due to weather. I think the pilots needed a massage before take off, what do the Chinese call it, shooting airplanes?

I was waiting for my flight this morning and two planes, one coming from Beijing and one coming from Dalian were delayed because of bad weather supposedly. I was flying from just down the road from Beijing, Shijiazhuang, And no delays for me. Thanks god!

It takes the pilot so long to figure out how to put the plane in reverse to get it out of the loading gate and onto the taxiing runway.

I was told that the military takes care of the air traffic and they basically don't give a rat's ass about who flies when..have no idea if it's true...

I almost missed my flight home because of Xiamen-Beijing flight delay. Everything is fine till we start queuing to board...dude says the plane is still in Hangzhou??!! Hahaaa, had to call my wife to come back to the airport as I was helpless...She talked to the duty manager, he found my luggage and put me on another flight, different airline!!! So all good in the end...I felt relieved...to say the least. 

Something on this here http://edition.cnn.com/2013/07/12/travel/china-airport-performance/index.html?hpt=ias_c2

https://www.scmp.com/video/china/2170130/chinese-man-slaps-airport-worker-his-iphone

5 days in jail, should be a month at least.