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While explicitly exotic states such as some of the tetraquark and pentaquark candidates seen in recent years are striking examples of hadrons not falling into the naive quark-model picture, there are also many states which could be simple quark-antiquark or three-quark states, yet traditionally pose a challenge to both model calculations and Lattice QCD determinations of the hadron spectrum alike. After providing some examples of such states, I will discuss the $\Lambda(1405)$, a strangeness $S=-1$ baryon with quantum numbers $I(J^P)=0(\frac{1}{2}^-)$. Specifically, I will present results from a recent calculation of the coupled-channel $\Sigma\pi$ and $N\bar{K}$-scattering amplitude. Our results in the $\Lambda(1405)$ channel support the picture of a two-pole structure suggested by theoretical approaches based on $SU(3)$ chiral symmetry and unitarity.