## 4 Discussion
Privacy concerns, among other privacy factors, affect not only users' intentions, but also their actual behaviors [57]. This indicates the reasons that participants invest low in capturing of social capital within SNs through self-disclosing, in contrast with previous findings [81], which show that users willingly provide this information in order to acquire the perceived benefits resulting from their networks. As [82] argue, the interrelation among disclosure attitudes and gaining benefits is not straightforward. Thus, participants rate their privacy concerns higher their needs for SNs services, indicating that their privacy calculus is not expected to change after a privacy violation, since they already respond with mechanisms, such the ones [83] proposed, namely, refusal or negativism. Up to this, considering that the relationship between self-disclosure and benefits is mediated by the factor of control of information [84], it was not surprising that the participants indicate the low degree of control on their information. However, as results show, they still upload information, for which they are not sure if it is proper for every audience to see or they do not take under consideration SNs privacy policies. After all, previous literature has already highlighted that, while users perceive highly their control over information, they usually ignore the control deriving by SNs policies over the information [85]. With this respect, an effective self-adaptive privacy scheme within SNs should provide users with plenty of control capabilities, enhancing their cognitive processes for implementing their privacy strategies. [77] emphatically support that self-adaptive privacy systems should provide users with adequate opportunities to express preferences and give feedback in relation to the privacy decisions they have to undertake. Nevertheless, ignoring privacy policies, a privacy risky behaviour, indicates another crucial aspect for the participants of our survey, concerning the necessity of the enhancing their privacy awareness. Participants estimate their privacy awareness in medium levels and consequently, privacy aware increase is of great importance to be provided by the designed self-adaptive privacy schemes. This becomes even more crucial, since according to [30], SNs incorporate basic privacy technical features, meeting only typically their responsibility for users' privacy protection, failing to address their complex privacy needs. Up to this, self-adaptive privacy schemes should provide users with the proper classified interaction strategies, facilitating the connection of the systems with them by proceeding to automated actions that enhance their privacy awareness and justify the privacy choices or decisions. This will strengthen users' privacy and it will enhance not only their awareness, but also their knowledge regarding the accessibility and use of information, deriving from SNs structure. What is more, our survey indicates that participants' information within SNs is comanaged and disclosed by other members of the groups they belong to, leading to risky behaviors, since the other group members do not take approval for disclosing information. As [62] argues, it is often unclear who and how many people are included in the groups, which disclose such information. Furthermore, it is also unclear who accesses and stores users' data, which are often analyzed by unauthorized parties [86]. Personal information disclosures of a user for other users, regardless other users' consent, like sharing friends,family, colleagues and other connections contact lists, enables SNs and third companies to misuse such information and circumvent users' privacy rights provided with GDPR, such as to know, to restrict processing, to not be subject of automated decision-making, leading to untrustworthy web services. Therefore, capturing the collaborative process of privacy management within SNs should be a great deal for the design of self-adaptive privacy schemes.