I look for a Dive Resort, not a Resort that offers diving. Liveaboards can fall into that same flip-flop category, notably from the Maldives to the SE Asian rim.
I look at their dive schedule with a critical view of how often I can actually access the diving.
It is one thing to "run" 5 dive boat departures per day. How many of them can I actually be on? Many resorts that cater to Eur-Asian divers have multiple dives offered that look enticing until you realize that it's all but impossible to do very many of them due to overlap.
I look for bottom time limitations also by looking at that schedule. I'm looking for a night dive each evening.
I look at their website and expect to see detailed images of their dive boats. If their website is devoid of "SCUBA details", it is very, very suspect immediately. There are also obvious signs of a "contrived and generic" SCUBA program that is simply inserted into the "activities" pages.
On land based, I do look for All Inclusive (AI), specifically to achieve the above with greatest efficiency. I do not want to luxuriate with 2 hour meals. The dive op should be under the same ownership. It should be getting consistent reviews over time.
On a liveaboard- can I just simply do the exact same diving more cheaply by doing land based? Is there sufficient "extra return" for going aboard or was I better off just doing day-dives from a land based? For many reasons, this distinction is invisible to many potential divers. Most of the marketing hype must be recognized for what it is. There are many liveaboards that provide no such benefit yet they make it through our susceptibility to the scuba magazine articles.
I try to look at the dive world from a different longitude. Do this by subscribong to dive magazines from England, Europe and some Asian countries. We look at the world from this North American Continent. If you see it from another perspective, it's even wider. The Brits think of the Red Sea as we do the Caribbean, they think of the Galapagos as we might look at the Maldvives. Conversely, they are attracted through heavy marketing to the Bahamas, an area of interest to us, but whould be travel 3000 miles?
Marketing will cause us to spend huge money and time to be "guaranteed" of seeing that "one big fish". I heartily counsel against that.