As a counter point to
elements of a losing sslnl player...
They do not play like a loser
They do not play like a losing player. Refer to the element of a losing sslnl player and basically insure that you are not doing any of these. Enough said...
They are properly rolled for the games they play in
There are two elements to bankroll.
One is the empirical logical part, i.e. risk of ruin (RoR) which has been well documented on 2+2, in books and websites. While some will differ slightly from another, let's sum it up to say you need X amount in your roll to avoid ruin.
The other often gets mixed into the empirical and logical thoughts and should not. That is the physiological side of money and poker. Everyone has different emotional responses to money, to winning money and losing money, to how much money they have in total, to how much money they have at immediate risk, to how much debt they have, to how large their monthly outflow is, etc, etc.
A winning player will always know what the minimum bankroll they need to have from a empirical and logical point of view to avoid a RoR situation. They will also know what they to have to be perfectly comfortable in the games they regularly play from a physiological point of view too. E.g. If a player is uncomfortable with less than 100 BI in their roll even though their RoR BI minimum is 20BI, they will maintain that 100+ BI roll.
Winning players are social
Some of the best live poker games are not the ones spread in a casino. They happen in private homes, rooms at the country club, in offices, etc, etc. Any arsehole can sit in a casino game if they have the minimum buy in for that game. Only someone who is known and to one degree/reason or another is liked is ever sitting at a table in the country club.
Remember that a lot of people play poker, it is a social network that goes way beyond the felt. You might find more opportunities than just at the felt if you act like a decent, friendly and honorable human being. No one likes to hang around a arsehole so don't be that person.
Winning players are humble and not prideful
Winning players are able to put their pride away in order to place themselves in the most +EV situations. They are willing to move down when the game conditions are not right, despite that they might be embarrassed by it. They are willing to quit the game when they are too tired to play even though a big fish still has money on the table.
Winning players are humble. Everyone hates a sore loser, but they hate a gloating winner even more.
If you need a good example, watch Durrr on HSP.
Winning players are able to analyse risk well
Analyzing risk is not just about figuring out odds in hands or taking shots at higher stakes games/MTTs, but overall in their life choices. They rarely find themselves in situations where they can be ruined or seriously damaged by their actions. They carry the appropriate insurance for their situation in life, they do not drive drunk, they do not play Russian roulette, etc, etc.
They are not afraid to take risks, not only on the felt but in life too. They have a kine understanding of the risk:reward ratio.
Winning players are never satisfied
Winning players are always striving to improve themselves, in poker and in life. They are not satisfied to just be carried along through time accepting what comes of it. They can be happy with themselves, but see that there is always some area or thing that can be improved.
While I do not coach regularly and only have had a handful of students, one requirement is that they are ready, willing and capable to devoting 5+ hours to study each and every week. If they can not live up to this requirement, they are out.
Winning players do not have to be God's gift to poker to be a winner
A winner is a winner is a winner. Rather you win at $20/hr at 1/2NL or $5/hr 1/2NL you are a winning player. I can not count the number of players I have seen that could be consistent winners at the stakes they are playing if they would just not trying to be God's gift to poker.
As a winning player we should always strive to better ourselves, however a winning player understands their limitations and the limitations of the given situation they find themselves in at the time.
For example let's say we need to improve our ability to get the maximum value out of the hands we play, and we feel that we need to work specifically on thin value betting. We should not be experimenting at our regular game when there is a stronger than normal line up. We should be working on this at lower stakes or when the line up abnormally weak. As we gain more skill then we should be trying to implement these skills in a normal game and eventually in the games when the line up is tough.
Winning players are capable of critical analyse of themselves
Winning players do not lie to themselves. They are able to take an uninhibited look at how they play, and how they live and act accordingly.
It is natural for humans to go thru a learning cycle. Early as we learn a new skill we struggle to understand and master the basics. Often someone learning a new skill will perform better after learning the basic concepts than later when they start to learn the details. At some point a deeper understanding and mastery of the details starts to come into play and we regain a level of performance that we seen when we first started. After much work and time we master the details and become truly skilled.
Poker is a combination of many skills, it takes time and practice to master. A natural and unfortunate part of the natural learning cycle is that we become "experts" long before we truly master a skill. But we are really not experts. An old saying in the IT world illustrates this well... "How do you tell a senior engineer from a junior engineer? Easy the junior engineer always knows the answer, while the senior engineer will always say something like 'humm I did not know that, tell me more...'". Do not be the poker expert, keep an open mind and critically analyse new information.