Find a domain expert and ask them to walk you through their day or shadow them. Also, ask them what sucks. I could literally throw ten ideas at you right now of fixable things of various complexity in my domain (academic bioengineering).
Another strategy is to look for large problems in your industry that have been solved and then try to find analogous problems in other industries where the same or a similar solution could work.
For our startup, my co-founder and I went and talked to friends and contacts of mine in medicine and generated a list of 15 or so things we thought were everyday pain points for many individuals. We then shelled out some money and went to an industry conference to field test them. It turns out that all of them were being actively worked on, but while we were exploring them we stumbled upon another idea which is now the basis for our startup.
Another strategy is to look for large problems in your industry that have been solved and then try to find analogous problems in other industries where the same or a similar solution could work.
For our startup, my co-founder and I went and talked to friends and contacts of mine in medicine and generated a list of 15 or so things we thought were everyday pain points for many individuals. We then shelled out some money and went to an industry conference to field test them. It turns out that all of them were being actively worked on, but while we were exploring them we stumbled upon another idea which is now the basis for our startup.