I have been traveling frequently for over 10 years. I have over 600 flight segments in the country and abroad and hundreds of other trips made by car, bus or train. I learned to optimize my luggage depending on the destination, the type of trip, the time of year and the weather conditions. It matters a lot if I go on a trip alone, with my wife or even in full formula with the children.
From experience I tell you that there are some things I have never put in my hold baggage and I recommend the same thing.
Do not put money in hold or hand luggage. The money must remain with you, in your pockets or in a purse / purse, etc. Better yet, always have money on you. If your luggage is lost or arrives late at your destination, you run the risk of running out of money :).
Don't put in luggage keys and cards. Obviously, for the same reasons mentioned above. You run the risk of losing them if your luggage is lost.
Also keep in mind that not all airports are safe and honest. Security staff may be tempted if they see a large amount of cash while checking your luggage. It will be difficult for you to prove the theft in such a situation.
Do not put travel documents, identity documents and other documents with sensitive information in your hold or hand luggage. If your luggage disappears, these documents will increase the risk of identity theft and quick access to your accounts.
Never carry products or items that are not yours. Whether your friends, relatives, or other acquaintances are asking for certain favors, my advice is to politely decline. You risk carrying various prohibited items or products for them and you will pay for the favor done. There have been cases in which innocent people have ended up in prison or have been fined for taking prohibited products in their luggage.
Do not put expensive jewelry and watches in your hold baggage. These items are easy to steal and you run the risk of running out of them, even if your luggage is lost. In general, it is best not to travel with valuables.
Do not put gadgets such as laptop, camera, external batteries in your hold baggage. First of all, these products can be damaged during the handling of luggage during loading and unloading. Also, if your luggage is at the base, imagine how much luggage is over your suitcase and what weight it should support.
And as we mentioned above, in some airports, these products can be stolen. There have been such cases even in Romania. Related to external batteries, be aware that they may catch fire. In the history of aviation, there have been cases with airplanes that landed in emergency mode due to a fire caused by external batteries. Unfortunately, there is also a case of a crashed plane powered by external batteries.
If you are flying to destinations in the US, Asia and other continents, Avoid carrying seeds, animal parts and other organic matter in your luggage. Organic items can be confiscated, and many countries have strict policies on organic substances and living things without a health certificate in their country of origin to ensure that living things are free of harmful microorganisms.
I recommend that the products mentioned above be carried or at most in the cabin luggage. I recommend that the gadgets be carried in dedicated bags - backpack / trolley.