This is a grey and complicated area. When serving a Section 8 Notice Seeking Possession under this discretionary ground, landlords need to carefully consider whether the evidence available will satisfy this ground and whether it likely the court will consider it reasonable to grant an Order for Possession in favour of the landlord.
The Courts will likley favour the tenant unless you can prove that serving notice under this section is warranted AND the detrimental effect it would have on your other tenants and/or the local community is realistic. Using Section 21 is usually a better option if you just want your tenant to quit. It's always better to talk to your tennant than go in with a poor Section 8. Remember, that tenants in a building will often target other, newer tanants they don't like in an act of cronyism due to false ideals, jealousy and personality clashes etc..
You should seek professional legal advice from a solicitor.