Having a disciplined approach to the markets simply means having a precise trading plan and following the plan to the ‘T’.
Now as a trader, one must remain flexible since the market will not always move the way we expect it to. This becomes contradictory & hence turns into a point of confusion.
Being flexible does not mean that one must abandon the discipline, but one must adapt one’s self to the changed situation.
Let’s take an example of an expected harmonic pattern which did not complete, and see how we must remain flexible.
I will go over the unfolding of the situation step by step to make things clearer –

Step.1 – We had a price retracement at the precise 61.8 fib level (B retraced to 61.8 of X-A) which indicated that we have a strong possibility of a bullish Gartley pattern forming.
(Please refer to previous posts for identifying and classifying the different harmonic patterns)
At this stage, this price formation can also be considered as a bullish 1-2-3 pattern.
Step.2 - As traders, we are looking for trades with high probability and we don’t predict the price action. We set down our alternatives and follow price.
Since price found support at a precise fib levels (the 61.8 of ‘X-A’), we can expect a rally to the upside.
Alternative.1 – We can expect an up-move to form the bullish Gartley pattern, and expect price to find resistance at point ‘C’ of the pattern…and give another move down.
We consider the 78.6 Fib retracement level (of A-B) as an important level & so long as price remains below this level, we can expect a down move
Alternative.2 – Price could continue with the uptrend to fulfill the price objectives of the bullish 1-2-3 pattern.
Conclusion – The probability of price rallying to the 78.6 Fib level (of A-B) is very high & one would enter a long trade till this level….at least.

As we can see, price rallied past the 78.6 Fib level (of A-B), which negated the Gartley pattern. Hence one would expect price to continue with the up moves and fulfill the price objectives of the bullish 1-2-3 pattern.

Every different situation demands an appropriate Fib ratio and we always use the Fib Expansions to determine the price objectives of a 1-2-3 pattern.

And price found resistance precisely at the FE 100 level.

Hence one would have managed the trade to get some nice long moves, simply by being flexible as per the situation.
One can call this the “If-Then” approach.
If price does this, then I would do that & if price does that, then I would do this.
But again, this “If-Then” situation has to have precise rules set down, which enable us to manage the trade to its logical conclusion.
Sunil.