223It is not because a concentration gives rise to synergies or cost reductions in favour of the merged entity that the transaction necessarily impedes competition. In addition, it is also not because a concentration creates or strengthens a dominant position, or that a single dominant undertaking decides on the merged entity’s competitive strategy and pricing policy throughout the national territory, that it automatically gives rise to a SIEC. The fact that a concentration would create or strengthen a dominant position is not, in itself, sufficient for that concentration to be regarded as incompatible with the internal market, provided that it does not significantly impede effective competition in the internal market or in a substantial part of it (see, to that effect and by analogy, judgment of 20 October 2021, Polskie Linie Lotnicze ‘LOT’ v Commission, T‑296/18, EU:T:2021:724, paragraph 107).