I am a big believer in going light and fast. There is even a rule for this: Rule 17: Simple and light equals freedom, agility and mobility.
Packing light allows you to move freely and to avoid many hassles while traveling. Packing light also allows you to adapt better to any situation. Your gear is minimal and you can reconfigure it to what the project needs. In cases where there is an emergency and a quick retreat is needed, having only a few things helps get ready faster.
When I'm travelling, even internationally, I just carry everything with me and I never check luggage.
On the way to the airport in Frankfurt, Germany, I was stuck in traffic for almost 1.5 hours. I barely made it to the airport in time, but because I only had a small pack I was able to return the rental car, run the big airport to my terminal, fly through security and make my gate with 20 min to spare.
Had I have a big piece of luggage, wait for the check-in line to drop the bag and get that boarding pass and then run to my gate, I would have never done it in time.
So, learn to pack light and remain nimble.
Here are some examples of packing light. Some for business, some for recon purposes, some for vacation and fun.
And some examples of packing lists. A sort of default go-to list of clothing for different trips.
The big problem arises when you need to bring gear. This in when knowledge and experience comes in. The more you do something, the more you know what works and what doesn't. The more you use gear, the more you know what's actually needed and what's redundant.
For gear, I tend to choose things that have more than one purpose, so I can bring less. For example, if I have a good scope during a physical recon trip, why brin binos? Add to that scope night vision, and now I also killed bringing a night scope.
Try to find the lightest versions of things you need, practice what you can do with them, and select what's needed and nothing more. Do not be tempted to bring all. Add until it's too much, then remove until you are left with the most minimal kit. Then you can go light.
Pack light and go fast. It works.