“High quality” comes up many times in many discussions here in Bitcoin talk.  The phrase “high quality” is sneaky and deceptive. The phrase itself tends to blind people even if the people who were using it weren’t trying to be deceptive.

According to a blogger, David Wiley, the core issue in determining the quality of any educational resource is the degree to which it supports learning. He said that when people say “high quality” they actually mean all these things (author credentials, review by faculty, copy edited by professionals, laid out by graphic designers, contains beautiful imagery, provided in multiple formats etc.) EXCEPT effectiveness.

So, “high quality” means effectiveness in educating others. If no merits have been given to you even if you think you are writing high quality comments and posts, maybe those are not as effective as they appear to be. Do not  always think whether you will be merited or not when commenting or posting. Rather, think about how you can help others and what you can teach them.

Perception of quality is subjective. What some may find interesting, some may find stale. The same goes with education, considering the different levels of knowledge and different interests people here possess. Merit awarding is also very subjective, as there are no guarantees you'll be merited even if you consistently post quality stuff.

That being said, helping others is good, but few people here actually need help. You certainly shouldn't be helping if you're expecting something in return. Just participate in the best way you can and the merit should come to you sooner or later.

Can I turn the question round and answer the question "What is not a high quality post"?

One annoying practice that I see with increasing frequency is a worthless necro-bump. If a new member necro-bumps a thread, it is extremely unlikely that his post will have any value, and it will probably just be a repeat of a preivously posted reply that he hasn't bothered to read. Necro-bumps are often fleshed out variations of the statement ' I agree'.

Note to newbies. When I am considering awarding a merit, I often look at post history. If I see that there are several spammy one liners, then I won't award the merit.  Merit is designed to prevent worthless spammers from achieving higher ranks, and I support that initiative.

I was going to make this same point. As long as the merits are in the hands of someone to give out, then the definition of which posts deserve merits will be based solely on the discretion of the person giving out the merits. What I find worthy of a merit could be completely different from what you find worthy.

Also, before now, I always felt it was almost impossible to get merits through comments but you have shown otherwise.

I absolutely agree with this and my ideas about giving merit are based on this:
A forum provides many functions beyond education, it's more a community of people with shared interests. Making a valuable contribution to that community can manifest itself in numerous ways that others will consider worthy of merit.

To be honest, it is a subjective term but considering the mass audience, we have generalized it and framed some parameters to classify any post as high quality. I have seen many posts that have added value to my knowledge but gained almost no merits, on the other hand, there are some worthless posts (in my opinion) are appreciated by some people. According to me, a general high-quality post is something that adds relevant value to the knowledge of the mass audience irrespective minor grammatical or layout mistakes (I am not supporting mistakes, one should always keep improving but I won't ignore the value of the post just because there is some grammatical mistake).