Why does the magnetic field stay continuous between stator winding positions?

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PhysicsTest
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TL;DR
Does the magnetic field rotate continuously or discrete.
I am analyzing the rotor magnetic field, i feel i understand the basic concept but have few clarifications.

1603550647150.png


At pt1, the net mmf due to currents
##i_a = i_{max}; i_b = -\frac{i_{max}} 2 ; i_c = -\frac{i_{max}} 2## is ##\frac {3F_{max}} 2##
1603550483841.png

Similarly i can do for Pt2. But my confusion is the region between the points pt1 and pt2, do i need to calculate similar to above. This question i am asking because if i see this website https://en.wikipedia.org/wiki/Rotating_magnetic_field ( i came to know from here) if share a screen shot from the website. The black arrow cannot stop in between the stator windings is my guess. Am I correct? What is the advantage of the continuous current in between pt1 and pt2?
1603550949200.png
 
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PhysicsTest said:
The black arrow cannot stop in between the stator windings is my guess. Am I correct?
If the currents are true sine waves then the magnetic field will be rotating reasonably smoothly.

As the current through two pole windings are momentarily equal as they pass, the two poles will have the same magnetic flux so the gap between will be magnetically invisible to the rotor as it passes.

If it was a stepper motor, fed with step currents rather than sine waves, then the field will step and the rotor would be able to be held between the poles.