The former Fulham manager, who has yet to agree a new deal with the Dragons, believes the side can qualify for future competitions if all their key personnel are fit and available
The 43-year-old has been without captain Ashley Williams and Gareth Bale, the world's most expensive player, for recent qualifiers, though the Dragons did record a 1-0 win over Macedonia on Friday.
Coleman insists his side could be challenging for a spot at a major tournament if he was able to field the strongest squad possible, and is keen for Wales to improve their seeding.
Wales are 40/1 with BetVictor to beat Belgium 1-0
“But I keep repeating that we can only do that with certain players being available more than they have been.
“I was pleased for the boys after Friday but it is one result and I always say we must look at the long term and that is qualification. In terms of this group we have to remember we came into it as sixth seeds and a sixth-seed team has never qualified."
Coleman has yet to extend his Wales contract and says the difficulties in trying to call-up his strongest possible squad, with many key players unavailable, matched with the fans' lofty ambitions, make the job particularly difficult.
“But when I think about my contract, whether to stay or not, and I ask myself how can I affect things going forward,” he added. “Do I want to deal with that kind of unrealistic expectations?
“I can see the reasons why I or anyone would want to lead this side forward because we have some very good players if they are all fit. But does it ever happen? I look at it and think if you are without too many players again how can anyone do anything about it?
“We came into this campaign on the back of a fantastic run under Gary Speed and the expectation was high. That’s great, I don’t mind that expectation but it’s an unrealistic pressure to say we should qualify. We have to have everything going for us to have a realistic crack at it.”