## 4 Discussion
Therefore, in this case, it could be deduced that the participants rated VR better in terms of quality transmission, which does not agree with the results after the second phase of the study. However, in the case considered as the third-most-important perception, \"Appeal\", it is observed that more than half of VR users find no difference between the perception in real interaction and that it is achieved through display technologies. On the contrary, AR users indicate a higher percentage of differences. This result is in accordance with the high ratings for the perception of \"Appeal\" through i_VR (and ni_VR, to a lesser extent), with respect to AR (Table 4, Figure 8). Something similar, although with less strength, occurs with the perception of \"Materials\", for which VR users find fewer differences than AR users. It should be highlighted that the most subjective perceptions, \"Reliability\", \"Quality\", and \"Appeal\", were valued mainly with \"Above\" (especially for AR), which means that they are perceived to a greater extent in the real product than through technologies. These results show the need to study whether the technologies can transmit not only the physical features of the product design but also those aspects that are more subjective, although they are probably more related to an attachment to the product. In short, the differences obtained in the perceptions of the real product, with respect to those generated from the technologies, indicate that the technologies analyzed in the study do not seem capable of offering an accuracy comparable to the interaction with the real product. This accuracy depends on the type of feature, the specific technology and display model, and the quality of the virtual representations (shape or details should be correctly replicated by the technologies, while shine or texture could be more dependent on the quality of the rendering), and it is expected to increase progressively over time. However, this comparison of the perceptions obtained from the technologies with those coming directly from the product is essential to be able to contrast the ratings about the technologies' capacity to transmit the features of the product. Moreover, it can be seen that the perceptions obtained by AR and VR users could vary depending on the type of product. For example, \"Dimensions\" and \"Weight\" seem to be better appreciated (more similarly to reality) by AR users than by VR users in the case of the gooseneck lamp, while this difference is not as noticeable for the sideboard. The same goes for the perception of \"Shine\", which is much better among AR users than VR users for the gooseneck lamp, while this difference is not appreciated in the case of the sideboard. Regarding \"Details\", while VR users detected fewer differences than AR users for the sideboard, the opposite occurs for the gooseneck lamp. AR users indicated that the real product presents fewer differences with the perception from the technologies. In any case, to obtain conclusive results, a larger sample size should be adopted. In conclusion, some results vary depending on the type of product and the feature considered. Therefore, it is not always possible to establish general guidelines on the best technologies to transmit certain perceptions. In contrast, some similar results have been identified for different cases. Thus, 360\({}^{\circ}\) is the display technology that has obtained the best ratings in most of the perceptions studied, so it seems appropriate when looking for general, not specific use. On the other hand, if the desired perception is specifically \"Appeal\", the results of this study indicate that i_VR is an appropriate technique for its transmission. Some of the results obtained in this study partially agree with other previous results in the literature, although some differences in the studies should be considered. For example, [PERSON] et al. [29] stated that the attractiveness of the product was greater in real interaction than through ni_VR.