Everything in holster design involves compromises among the 4 basic factors of comfort, accessibility, security, and concealment. Whenever on factor is emphasized there will be compromises in the other factors.
Cross-draw carry can work very well for those who are regularly seated in a chair, driving, or suffer range-of-motion issues (shoulder, elbow, wrist). However, there can be trade-offs in accessibility, in concealment, security, or all three.
Cross-draw usually requires that the grip-frame of the handgun be angled toward the front, otherwise drawing the weapon can require difficult or awkward hand and wrist positions that cause reduced grip strength due to excessive rotation of the wrist. With the handgun canted butt-forward concealment can become much more of a challenge, usually requiring cover garments that must remain closed at the front, thus further reducing accessibility. Also, canting of the handgun results in moving the grip-frame into closer proximity with the belt and waistband, which can make it more difficult to achieve a good grip on the weapon during the draw.
Finally, carrying in the cross-draw position exposes the weapon more to any potential opponent, making it much easier for the drawing motion to be blocked or for the weapon to be snatched away. Simply reaching across the front of the body to draw the weapon will clearly telegraph your intentions to a potential opponent.
There is nothing inherently wrong with cross-draw carry, but the limitations should be kept in mind while doing so.
