I have looked for previous posts but found nothing so I am asking anew hoping for starting point to an answer. Chain keeps dropping to the inside on an 2014 Orbea 11 speed. At first I was recommended to take precautions and keeping the bike in certain gears while transporting. Next the chain dropped while unclipping. Lastly, the chain dropped while riding. I have just installed a chain catcher and upgraded to a dura ace chain but I want to know what is at the root of the chain dropping.
I had the same issue on my bike and just put the chair catcher on, and not change gears working hard up a big hill.
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Could be a few things, but check your limit screw for the inside of the front derailleur, likely you are moving the chain too far inwards upon shifting especially if that is when it mostly happens.Also check to see if the cable tension is correct (should be relatively tight on your left side chain near the downtube going to your front der. Or it could even mean you too many links in your chain causing it to have less tension than it should and prone to rattle off from time to time.
Youtube has a lot of good videos on adjusting your front derailleur as a starting point.
And yes, a chain catcher is a good device to aid with chain retention on the inside.
A local shop may have a few other suggestions as well.
j
Have your shop check for chain wear. Depending on your miles and wattage, chains can last a few weeks to a few months. If it stretches beyond the tolerance limit, it will ruin you cassette. Chain dropping to the inside when you unclip is how I know I went too long without changing chains 
Chains last way longer than “a few weeks to a few months.” Your local shop must love you. This year i am so far on 11,500 miles on my road bike and put 7500 miles on the first chain and the rest on a second chain, and i am not easy on my chains either. Even if you never lube and clean your chain they will last thousands of miles before having any kind of issue. I have put over 10k on an old ultegra chain and started dropping chains, went with a new DA chain and it was still dropping, ended up being my limit screws were slightly off and i was just shifting at the wrong time (high tension while in the worst gear).
Edit: there might be some exceptions with very high end lightweight chains/cassettes but in general a high quality chain will last a very long time. I switched to KMC (their 80 dollar chain) and that sucker lasts forever, but even their middle of the road chain (40$) has given me close to 8k miles before clearly needing to be retired.
Chains last way longer than “a few weeks to a few months.” Your local shop must love you. This year i am so far on 11,500 miles on my road bike and put 7500 miles on the first chain and the rest on a second chain, and i am not easy on my chains either. Even if you never lube and clean your chain they will last thousands of miles before having any kind of issue. I have put over 10k on an old ultegra chain and started dropping chains, went with a new DA chain and it was still dropping, ended up being my limit screws were slightly off and i was just shifting at the wrong time (high tension while in the worst gear).
Edit: there might be some exceptions with very high end lightweight chains/cassettes but in general a high quality chain will last a very long time. I switched to KMC (their 80 dollar chain) and that sucker lasts forever, but even their middle of the road chain (40$) has given me close to 8k miles before clearly needing to be retired.
While I agree with you that a few weeks to a few months is too low, leaving your chain on for 7500 miles is going to the other extreme. If you replace your chain regularly you can make your cassettes last a lot longer. Leaving your chain on for a long time means you have a good chance of needing to replace your cassette at the same time. You should measure your chain and if it has elongated significantly, replace it. I replace the chain on my tri bike once a year, which means about 3-4K miles. I ride my road bike much less, and only replace the chain every 2-3 years. As a result I’m able to get many years of use out of my cassettes.
It also depends on the conditions you ride in. If you ride in the rain a lot you’ll wear out your chain a lot quicker than if you ride in the desert.
I kept dropping the chain on my Orbea and after much frustration I found the cause, a stripped bottom bracket (drive side cup was moving in and out under load) which allowed the crank to move and drop the chain.
I wont go into the fact Orbea wouldnt warrant my frame…
The root is a badly tuned setup. Even cheap chains on cheap cogs will stay on when setup correctly.
Properly adjusting your limit screws on the front derailleur and the chain catcher (that has to be properly adjusted too) should keep you from dropping in all but the worst circumstances. It worked for me.