Why do I keep losing to weaker players?
It sometimes happens in chess that a significantly weaker player than you beats you regularly, ie "he has your number". This is true even for grandmaster level players.
In my case, I can drop upto 100 plus points at a stretch, losing game after game, mostly to players rated lower than myself (often dropping 10 -12 points per loss) on chess dot com. I grimly work my way back to 1700 something, then again it is a free fall of 100 points. My games, even lost ones, against higher ranked players are of markedly better quality. This is an expensive weakness and deserves some analysis.
After 900 games under my belt, I am finally getting an idea of what is going wrong: a lack of healthy respect for an opponent ranked 50, 100, or even 150 points lower. These ladies and gentlemen may be substantially lower in their ratings, but being chess players, their killer instinct at the board is no lesser for that; they want to win very badly. Players down the rankings are progressively less strategically inclined, but are often good tacticians, and remain fully focussed even in dull situations because they are always on the lookout for tactical opportunities, unlike the more staid strategic types who play positionally with long term objectives. This leaves some of the latter vulnerable in sharp, unfamiliar positions and if the complacent player takes it easy, brewing a cup of tea or rustling up a snack and reaches middle game about equal, he gets an unpleasant surprise, for, as the game simplifies, it starts getting more and more evenly matched.
It is also true that even an extremely good tactician will rarely cross much beyond the 1600 mark as strategic skill becomes increasingly necessary to play successfully beyond this level. Yet, he will always have good chances against chess players who may be higher rated, but who are not sufficiently rounded to be comfortable in unconventional positions, specially early in the game.
I have modified my approach, and have now started playing with full concentration against all comers, not only the heavyweights, having reached a genuine realization that I can very well lose to a considerably 'weaker' player if I slacken and that every win in a game of chess has to be fully earned. Attacks along long diagonals from remote corners of the board are easy to overlook if one is not on full alert like against a stronger player, as also discovered attacks when a piece is inoccuously moved out of the way. Another deadly maneuver easily overlooked on a crowded board is the moving of the queen sideways right across the board to attack along an acute diagonal. Such blunders aside, it is also never wise to dismiss your weaker opponent's move as aimless woodpushing and reply without being clear about his objective.
However, the biggest headache is boredom, sheer mind-numbing boredom, when a 'won' position goes on and on. To my mind, there is nothing as tedious as actually mating your opponent in a hands down winning position, say a bishop or an exchange up; players ranked 1700 plus invariably resign fast when they can see that defeat is inevitable. End-games, in which the board is very sparsely populated, with pawns and a minor piece or two I have found require a different kind of chess thinking, and an otherwise resourceful player can suddenly find himself devoid of ideas in such a situation even when he has an edge in material.
My aim is to be consistent in all stages of the game, and also play my best against opponents of all levels. I have stopped aborting games against opponents even 200 points lower, treating such games as essential for improving my chess temperament. But changing old, deeply rooted attitudes is hard.