body: What exactly does **otherwise** mean? What are the **other wises**? [wise](https://law.stackexchange.com/q/47147/25327) means manner/extent.
  
  
  [*O'Sullivan & Hilliard's The Law of Contract*](https://www.amazon.co.uk/OSullivan-Hilliards-Law-Contract-Janet/dp/0198807821/ref=dp_ob_title_bk) (2018 8 ed). p 106.
  
  
  
  > 
  > 5.55 Furthermore, there are several more general problems with the decision in [[*Roffey*]](https://en.wikipedia.org/wiki/Williams_v_Roffey_Bros_%26_Nicholls_(Contractors)_Ltd):
  > 
  > 
  > • Fear of duress might not be the only reason for the rule in *Stilk v Myrick*: it may
  >  also operate to encourage parties to price their contracts properly in advance.
  >  As O’Sullivan (1996) points out: ‘Why should any contractor bother to estimate
  >  his price accurately or supervise his staff, now that the law is willing to treat his
  > 
  > 
  > 
  
  
  p 107.
  
  
  
  > 
  > difficulties in performing his contractual obligations as a sufficient “reason” for
  >  enforcing a subsequent promise to pay him more than the contract price?’
  > 
  > 
  > • Those who criticise a consideration requirement in this context point out that many
  >  contracts, rather than embodying a one-off transaction, are in fact long-term relational
  >  arrangements, which must be allowed to develop with the parties’ relationship
  >  over time. In such cases, the requirement of consideration for each variation
  >  is unrealistic and, it is said, should be modified to meet commercial reality. One
  >  response is to say that, if properly drafted, such relational contracts can contain
  >  their own mechanism for alteration over time (like a rent review clause in a long
  >  commercial lease). But more fundamentally, of course, the point is that *Roffey* was
  >  not such a contract anyway—it was a one-off job for a price.
  > 
  > 
  > • Commercial parties need certainty. Supporters of the *Roffey* approach say that it is
  >  nonsense that a contractual variation is enforceable if the other side’s obligations
  >  are altered in a trivial way, **but not otherwise**. But that is at least a fairly straightforward
  >  way of making the variation work, allowing for clear legal advice at the
  >  time and thus avoiding litigation later.
  > 
  > 
  > • Finally, it should be noted that those who advocate the abolition of consideration
  >  for contractual variation do not necessarily agree with the approach in *Roffey* that
  >  practical benefit suffices for consideration. For example, the New Zealand Court
  >  of Appeal has since gone further and decided that contractual variations, once
  >  relied on, do not need consideration at all (see *Antons Trawling Co Ltd v Smith*
  >  (2003), noted by Coote (2004)).
  > 
  > 
  > 
  
  
  
title: Why's it nonsense that a contractual variation is enforceable if the other side’s obligations are altered trivially, but not otherwise?