The real test of teaching is whether the pupil retains the wisdom they have imparted.

If the educational tips go unheeded, then a different tack must be used until an efficient method is found.

If lessons continue to go unlearned, then the blame must fall on the teacher.

Thus, our 2-1 defeat against Watford may have been unlucky, but this tired performance we have all seen before but the source of our defeat lies at the feet of Arsene Wenger.

Comfortable at 1-0, coasting through the second half and with multiple opportunities to giftwrap the points and head back home, Arsenal had possession locked up and were cruising.

So, the turnaround in the last 25 minutes is hard to swallow. Watford were allowed to get back into the game. They didn’t show a herculean effort to dismount us from our winning horse. They didn’t dazzle our defence to unlock our backline which hadn’t conceded for over 440 minutes.

No, they got back into the game because we allowed it - and this is the lesson that our team refuses to attend, or acknowledge. Season after season of the same pattern. Dominate possession, create enough to win the game. Waste those chances and then take our boot from the neck of our opponent and invite them to stand up and start swinging.

This sort of display happens from time to time with the likes of City, Chelsea and United. It isn’t permitted to happen with the frequency we seem to manage however.

Our defence was without the injured Shkodran Mustafi, but Per Mertesacker was holding his own. The back three stifled when required and were calm under the small pockets of pressure Watford managed to apply.

We deservedly took the lead thanks to Mertesacker’s header from a Granit Xhaka corner. Then, Iwobi, Welbeck and Lacazette were denied or finished poorly as our lead stayed as a one goal margin. At half-time, there didn’t seem to be an inch where the Hornets could jam their foot in the door.

We had this game locked down. We faced just three shots on target in the 90 minutes. The first one didn’t come until the 65th minute. It was the attack in the 70th minute which heralded the equaliser - and there was contention regarding its merits.

The young Brazilian Richarlison attempted to cut in but was shadowed closely by Hector Bellerin. They continued into the box, shoulder to shoulder, and Richarlison pushed the ball ahead of him and then went down.

There was contact, and the majority of pundits have said that. Since when does contact mean a penalty though? Did Hector truly impede the Brazilian? No. Did the Watford man go down easily? Yes. It was not a penalty, just as the majority of penalty incidents these days are not penalties. Yet the referee Neil Swarbrick was swayed and awarded the spot kick.

Petr Cech has not saved a penalty since 2011, and again he was easily fooled as Troy Deeney scored.

It was an even game from this point. We had given Marco Silva’s team a foothold and they were using it. We still had chances, but as the game wore on towards the dying embers, we retreated. That shows a lack of ambition. We are The Arsenal, and we should be fighting for maximum points, yet in the last ten, we were stymying Hornets.

Etienne Capoue very nearly grabbed the winner with a wickedly deflected shot that deceived Cech but hit the post. Watford were not to be denied though.

Just beforehand, Laurent Koscielny, a fitness doubt before the game, signalled to the bench that he could not continue. This happened just as Jack Wilshere was about to come on for Alex Iwobi. The planned substitution had to be rearranged as Rob Holding came on for the French defender, but it made no difference. I have noticed people on social media attacking Wenger for this, but it could not be helped. The majority of us would have played Koscielny if there was a small chance of him getting through the game.

The result though? That is all Wenger’s fault. The winner came courtesy of Tom Cleverley, who blasted high into the net and set off raucous celebrations amongst the home faithful.

Yet again, we were bested by a team that should have been worm-food after the first half. Troy Deeney came out after the game and gave a savage assessment of our side, claiming we lack cojones. While the manner in which he delivered his remarks leaves a lot to be desired, can we say it is wrong?

Put a 1-0 lead and possessional dominance in the hands of any other top4 rival team, and nine times out of ten, they will see out the game. People point to the penalty, including Wenger, which turned around Watford’s fortunes. It didn’t.

This game is a carbon copy of twenty, perhaps thirty losses in the last decade, where we have had our opponents on the rack, but failed to finish them off. We are not ruthless. We seem unable to keep up our tenacity levels for 90 minutes. This hurts us, as if we do not have a two goal cushion or more, it is an open invitation for teams to hit back.

Our defence were not to blame, they have been fantastic recently. Our midfield nor our attack were at fault. Arsene Wenger is, for failing to deliver the lesson which continues to hurt us.