<p>This research investigated why the same material has different failure strengths depending on the applied loading type, such as axial and bending loading. In other words, the same materials have higher flexural strength than tensile strength. The major difference is that uniaxial tensile loading results in uniform stress across the specimen, while bending loading yields a stress gradient through the thickness. A recently proposed failure criterion shows that stress and stress-gradient conditions must be simultaneously satisfied for a material to fail. Satisfying only the stress-based failure condition is a necessary but not sufficient condition for failure. The standard tensile specimen already satisfies the stress-gradient condition because of zero stress gradient across the specimen. On the other hand, the bending specimen must satisfy both conditions simultaneously. The failure stress resulting from the stress-gradient condition is generally greater than the failure stress from the stress condition. This results in higher flexural strength than tensile strength. To validate the different failure stresses between tensile and bending loads, two sets of experimental tests were conducted using 3-D printed specimens. The specimens were subjected to axial, bending, or their combined loading. Their experimentally measured failure loads compared very well with the predicted failure loads using the proposed failure criterion, regardless of the different loading types. The flexural strength can be predicted using the stress gradient failure condition.</p>